The best resource(s) depends on how much time you are willing to invest into your chess, how much money you are willing to invest and how much effort you are willing to invest into your chess.
Obviously, playing a bunch of games, analyzing them and then rinse and repeat requires a lot of time and motivation. As for money, if you have an overwhelming amount, then of course getting chess coaching becomes a faster way of learning and then finally how much effort you can invest into chess comes down to your level of effort and personal life schedule to make time and desire for that chess increase.
Across most levels of chess rating, you can learn completely free (or at minimal cost), but it will often times still take a lot of time and effort...years for really significant changes.
Some generally accepted ways to improve are:
- Playing a lot of games and analyzing them (with and without a computer have their merits, but the key is to get quick feedback that is quality and then learn from past mistakes)
- Solving lots of chess puzzles/tactics (to increase tactical ability and pattern recognition)
- Lots of chess "study" which could mean reading chess books, or watching free YouTube videos or a list of other things
What are your best resources (chessable courses, online platforms, certain online courses, books, etc.) and methods (focusing on a specific aspect of chess, having certain specific goals, etc) that have helped you or is helping you rapidly improve your rating in chess?
And for methods, let's pretend I have infinite effort and money to put into chess, but not a lot of time. How would I go about for that?
Also, for the best "resources", I want to know specific names of books, platforms, etc. that you would recommend to anyone and everyone because they have helped you improve tremendously.