Where else to learn
wannacode is not the only place to learn C#, and it does not try to be. Here is where to go on when you want more.
SoftUni
Section titled "SoftUni"Software University (SoftUni) is a Bulgarian school for programmers: courses from the basics to a job, with exams, teachers and a large community. A good place if you want to learn in a group, on a schedule, with people who review your code.
The official documentation
Section titled "The official documentation"Microsoft Learn: C#: the official documentation and tutorials by Microsoft for the language and .NET. When a lesson here gives you the idea, the documentation gives you every detail.