I can't recommend enough lichess.
It's been featured on HN numerous times [0]. Will always be free and has an extremely interesting tech stack.
Note: lichess isn't just about playing chess with other people online. They have great "training" section (e.g. how to mate in X moves, pick the best move available, etc). I almost enjoy the training section more than playing against someone else.
Puzzles are good for when you're still learning how to look at basic things: forks, pins, etc. etc. But you need lots of experience in-games (especially with the "lack of knowledge" about whether or not a pin is possible in any position).
Puzzles are much easier than playing a game. Focusing for just 1 to 2 minutes on a particular board state is much less tiring than focusing for an hour over a "Rapid" game.
Many like me enjoy puzzles because it a problem to solve like any other type of pzzule not because it helps in the learning the game.
Knowing that a puzzle(chess or regular) has a solution does not take away the joy of solving it.
Code probably isn't ideal as this is my first time messing with React, but I'm hoping some people find it useful. I need to automate keeping the db updated as well, it's a couple months behind latest lichess open db.