Playing:
https://lichess.org/ → Open source, Ad-free chess server. It features tactics, opening and coordinate trainers. Blitz, atomic, 3-check, horde, chess 960, King of the Hill; standard or antichess, live or correspondence. 100% free, no premium accounts to speak of. It's the best site for playing chess at a club level, the only downside is a smaller player pool. It runs stockfish 8.
Channels:
https://www.youtube.com/user/STLChessClub → Lectures by titled players
https://www.youtube.com/user/thechesswebsite → Openings, key concepts behind them, some middle game theory
https://www.youtube.com/user/KebuChess → Openings (with a lisp)
https://www.youtube.com/user/kingscrusher → Analysis of master games
https://www.youtube.com/user/ChessNetworkhttps://www.youtube.com/user/chessbrah → Eric Hansen's channel, not very instructive but somewhat entertaining
Required reading (I am not sure I can post links):
-Matanović's Encyclopedia of chess openings
-My system by Aron Nimzowitsch
-Kasparov's Chess Puzzle Book
-Dvoretsky’s Analytical Manual
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