I liked Dirac’s problem sets as a guide for me to understand GTR.
I am not saying it’ll work for you, but I endorse rigorous engagement with a field of thought I’m interested in.
Dirac is problem set oriented, very dry. A more update book might be preferable.
Passively reading or listening to music is not going to make you a pianist.
So work problems and challenging my idea.
Through that you’ll find what tools and the building blocks you need.
Remember this:
Einstein didn’t solve the field equations or prove GTR. His work was exhaustive enough as he proposed a whole new universe over Newtonian classical views.
Einstein proposed GTR after he spent 10 years learning a whole new way to think.
Einstein’s STR was “restrictive” in a way that allowed him to express space-time without all of the implications of gravity and other forces.
Riemann was hard for Einstein to understand too.
Non-Euclidian is just a word, the reality of it is much more.
Good luck, my friend!
https://www.amazon.com/General-Theory-Relativity-M-Dirac/dp/069101146X
Dirac's book on general relativity, a small booklet with 69 pages (nice). Jokes aside, no one would use something this thin to learn GR, it's more of a reference book.