Everything you need to install, configure, and run your first C# application with .NET 10.

Imagine you've just bought the most powerful power tools in the world — but they're still in the box, and you don't have a workbench.

You can't build anything until you set up your workshop.

That's exactly where we are right now. You've learned what C# and .NET are. Now it's time to set up your development environment — the workshop where you'll write, build, and run C# code.

By the end of this page, you'll have a fully working .NET 10 environment on your machine, and you'll have run your very first C# program.

What Is the .NET Development Environment?

The Simple Explanation

Your development environment is the set of tools you use to write and run C# code. It includes:

• The .NET SDK — The engine that builds and runs your code
• A code editor — Where you write your code (VS Code, Visual Studio, or Rider)
• Extensions / plugins — Extra tools that make coding easier

The Technical Definition

.NET SDK (Software Development Kit) is a collection of tools, libraries, and runtime components that allow you to create, build, and run .NET applications. It includes:

• The CLR (Common Language Runtime) — executes your code
• The BCL (Base Class Library) — pre‑built code for common tasks
• The compiler (csc) — translates C# to IL
• The dotnet CLI — command‑line tools for creating, building, and running projects

Why Do We Need to Set This Up?

The Problem

If you just write C# code in a plain text file, your computer doesn't know what to do with it. It's like handing a builder a blueprint with no tools, materials, or instructions. The builder needs:

• A way to understand your code (compiler)
• A way to run your code (runtime)
• Pre‑built parts to avoid reinventing everything (class library)
• A place to write your code (editor)

The Solution

The .NET SDK and a good code editor provide everything you need in one cohesive package.

Big Picture — What We're Building

Here's the complete setup we'll create:

How It Works — Step by Step

Step 1 — Install the .NET 10 SDK

Go to dotnet.microsoft.com/download and download the .NET 10 SDK for your operating system (Windows, macOS, or Linux).

Verify it's installed correctly by opening a terminal (Command Prompt, PowerShell, or Terminal) and running:

dotnet --version

You should see something like 10.0.100 (or a similar 10.x version).

Step 2 — Install Visual Studio Code

VS Code is a free, lightweight code editor that works on all platforms. Download it from code.visualstudio.com.

Step 3 — Install C# Extensions

Open VS Code, click the Extensions icon (left sidebar, looks like four squares), and search for:

• "C# Dev Kit" — Microsoft's official extension pack (includes C# extension, IntelliCode, and more)
• Alternatively, install the "C#" extension by Microsoft directly

Step 4 — Create Your First Project

Open a terminal (in VS Code: Terminal → New Terminal) and run:

dotnet new console -n MyFirstApp

This creates a new folder called MyFirstApp with a complete C# console application.

Step 5 — Run Your App

Navigate into the project folder and run it:

cd MyFirstApp
        dotnet run

You should see:

Hello, World!

You've just written and run your first C# program!

Simple Example — Your First Program

When you run dotnet new console, it generates a Program.cs file that looks like this (using the modern top‑level statements syntax in .NET 10 / C# 14):

// Program.cs — Your first C# program
            Console.WriteLine("Hello, World!");

What's happening here?

• Console.WriteLine — A built‑in .NET method that prints text to the terminal
• "Hello, World!" — The text we want to display
• The ; — Every C# statement ends with a semicolon

In .NET 10 (C# 14), the compiler automatically generates the Main method entry point behind the scenes, so you don't have to write it yourself. This is called top‑level statements — a modern convenience that keeps your code clean.

Project Structure Breakdown

Real‑World Example — Building an E‑Commerce API

Imagine you're building a backend API for an online store. Your development environment would look like this:

• .NET 10 SDK — Provides the runtime and libraries
• VS Code — Your code editor
• C# Dev Kit — Intellisense, debugging, and project templates
• dotnet CLI — You'd use commands like:
  • dotnet new webapi -n StoreApi — create a new web API project
  • dotnet add package Dapper — add a database library
  • dotnet build — compile the code
  • dotnet run — start the API server

This same setup — one SDK, one editor, one set of tools — powers everything from tiny console utilities to massive enterprise systems serving millions of users.

Analogy — Setting Up a Kitchen

Think of setting up your .NET environment like preparing a kitchen before cooking a big meal.

Without the SDK, you have no "appliances" — your code can't run. Without VS Code, you have no "work surface" — writing code is clumsy. Without extensions, you're using dull knives — everything takes longer. All three pieces work together to make you productive.

Under the Hood — What dotnet run Actually Does

When you type dotnet run in your terminal, a whole chain of events happens behind the scenes:

Important: The build and run steps happen in separate phases. You can also run dotnet build to compile without executing, and dotnet run --no-build to run without recompiling.

Common Confusion

SDK vs Runtime — What's the Difference?

This is a very common confusion. Let's clear it up:

Correct relationship: As a developer, you install the SDK. It includes the Runtime. For production servers, you typically install only the Runtime (or the ASP.NET Core Runtime for web apps).

Common wrong thinking: "I installed the .NET Runtime, why can't I run dotnet new?" — because dotnet new is an SDK command, not a runtime command.

VS Code vs Visual Studio — Which One?

Common Mistakes

Mistake 1 — Installing the Runtime instead of the SDK

Wrong: Downloading ".NET Runtime" and wondering why dotnet new doesn't work
Correct: Download the .NET SDK — it includes everything you need

Mistake 2 — Forgetting to reload VS Code after installing the SDK

Wrong: Installing the SDK but seeing errors in VS Code
Correct: Close and reopen VS Code (or reload the window) so it picks up the new SDK path

Mistake 3 — Not using the terminal inside VS Code

Wrong: Opening a separate terminal window and navigating to the project
Correct: Use Terminal → New Terminal in VS Code — it automatically opens in your project folder

Mistake 4 — Ignoring the obj/ and bin/ folders

Wrong: Editing files in obj/ or bin/
Correct: Only edit source files (Program.cs). The obj/ and bin/ folders are generated by the compiler — never edit them manually.

When Should I Use This Setup?

This setup is perfect for:

• Learning C# and .NET — Lightweight, fast, and beginner‑friendly
• Web development — Building APIs, websites, and microservices with ASP.NET Core
• Console applications — Automation scripts, CLI tools, background services
• Cloud development — Deploying to Azure, AWS, or any cloud provider
• Cross‑platform development — Build once, run on Windows, macOS, and Linux

Consider a different setup for:

• Large enterprise solutions — Visual Studio Enterprise may be better for massive codebases
• Mobile development with MAUI — Visual Studio provides better tooling for mobile
• Game development with Unity — Unity has its own integrated tools

Mental Model

Remember:

• SDK gives you the power to build and run
• VS Code gives you a comfortable place to write
• Extensions give you superpowers — IntelliSense, debugging, refactoring
• dotnet CLI is your command centre — create, build, run, test, publish

Key Takeaway

Check Your Understanding

You've set up your environment and run your first program. Let's make sure you understand the tools and commands.

Your .NET workshop is ready! You have everything you need to start building real applications.

dotnetmadeeasy.com — Learn C# and .NET, the right way.