Free course on Microsoft Learn
Microsoft's Build .NET applications with C# is a free course on Microsoft Learn teaching how to build backend applications using .NET and C#. You learn ASP.NET Core fundamentals, dependency injection, entity framework, and building APIs. After finishing, you can build production-ready web applications. .NET is Microsoft's platform for building web services, APIs, and business applications. The main limitation: this assumes C# basics. If you're new to C#, take the C# for Beginners course first.
ASP.NET Core, the web framework this course centers on, is used by 21.3% of professional developers, ranking just behind Next.js among backend frameworks (source: Stack Overflow Developer Survey 2025, Web Frameworks and Technologies section, survey.stackoverflow.co/2025/technology).
Microsoft Learn's end-to-end .NET path. Covers building console apps, web APIs with ASP.NET Core, working with Entity Framework, and deploying to Azure. Interactive exercises throughout. Free with a Microsoft achievement.
C#Beginner
Microsoft Learn's official C# learning path. Covers syntax, variables, methods, classes, collections, LINQ, and async programming through interactive browser-based exercises. Free and earns a Microsoft achievement on completion.
C#Beginner
freeCodeCamp's complete C# course with Mike Dane. Covers the core concepts of C#: syntax, OOP, collections, exceptions, file I/O, and LINQ. A solid on-ramp to C# and the .NET ecosystem. Free on YouTube.