TypeScript has a Turing complete type system so it's as powerful as it gets in terms of what can be expressed in the type system. As for learning and understanding what is going on with type systems in general you'll have to go through a textbook if you really want to develop an understanding. Type systems (not Turing complete ones) are fundamentally logical systems and I don't know how you can understand type systems without actually going through the trouble of understanding the underlying logical fundamentals.