Try .NET is an interactive documentation generator for .NET Core. 

Use Try .NET to create executable C# snippets for your websites or, interactive markdown files that users can run on their machine. 

Try .NET execute C# code in client side using Blazor and Web Assembly. 

https://github.com/dotnet/try 

Build Real App in Angular 10 and ASP.Net Web API

These are 2 of the hottest frameworks right now for the ‘back-end’ (Microsoft’s ASP.NET Core) and the ‘front-end’ (Google’s Angular) and are well worth spending the time to learn.
This course starts from scratch, you neither need to know Angular 1 nor Angular 2
We will start from nothing and incrementally build this property dealing application front-end using Angular 10.
And then we will connect our front-end with the Web-API until we have a fully functional Web Application that we will publish to Firebase and then on IIS.

The Problem

What they neglect to say is all that testability and persistence ignorance flies right out the window when you create a new ASP.NET Web Application using the MVC template and "Individual User Accounts" authentication. What you get is a single-layered application, tightly coupled to Entity Framework, that:

• Ignores the patterns that facilitate testing, including: the repository pattern, unit of work pattern, and dependency injection;

• Forces you to implement their IUser interface in your application’s User entity, thereby coupling it to ASP.NET Identity;

• Eliminates any clear separation between your entities, persistence concerns, and business logic. Persistence ignorance? Forget about it.

Thankfully, due to the extensibility designed into ASP.NET Identity, it is possible to ditch the reference to the Microsoft.AspNet.Identity.EntityFramework assembly and write a custom implementation that can address these and other architectural issues. Just be forewarned: it is not a trivial undertaking, and you’ll have to put up with some code smell that is baked into the Microsoft.AspNet.Identity.Core assembly.