What sould I learn after finishing C basics .I mean, is there anything else I should learn?

That's a bigger question than you think!
The "C basics" are just that: basic. C is an old language, and very, very few new projects are written in it theses days - it has been superseded by languages such as C++ (object oriented C, powerful but a lot more complex than C), C# (object oriented, powerful, looks like C to a large extent but is very very different under the skin), and languages which are (pretty much) specific to the platform (objective C / iOS, java / Android for example)

So "what to learn" to create a little game isn't as simple as "this" - it's going to depend to a huge extent on where you want to run your game!
If it's a console game (a text adventure maybe) then C will work fine (but you'll have to do a lot of work yourself on file storage, probably).
If it's a Windows game, then C is a bad idea: C++ or C# would be better (and I'd suggest C# as it's a lot more "beginner friendly") - you can write Windows apps in C but it's a lot of hard work! You will have a lot to learn about the frameworks and how it all fits together to get anything much up and running.
If it's a mobile phone game, then either C# with Xamarin, or the phone's native objectiveC / Java is the way to go: expect a huge learning curve!
If it's an online game (or worse, multiuser online game) then you are throwing yourself in at the deep end, and tying huge weights round your ankles first!

So think about what you want to produce and the environment it is to work in, then start working out what that needs. There is no "one size fits all" route that you can just learn, I'm afraid.