I want to learn chess


Hang around here for a while. Read a bunch of articles for beginners under the "Learn" tab. Play through a few Master games under the "More" tab. Try out some of the simple checkmate drills (Q + K vs. K and 2 Rooks + K vs. K) under the "Puzzles" tab. Play a couple of games against one of the lower rated computer opponents, say 600, with all the help buttons checked. It makes no sense to join here and then immediately ask what to study first. This site is filled with thousands of puzzles, games, articles, and competition go get you well under way.
After you've done all that, then your questions might be a little more specific.

Highly recommend trying the lessons on Chess.com and analyze your games. Check the analysis for suggested lessons and try those. Some learn by feel though, so as you play, if you're doing book moves by pure coincidence, I think that's an indication that you possess some natural intuition and may learn by playing game after game.
There are so many ways to learn to play chess, it's just a matter of finding what works best for you. I definitely recommend checking out GM streamers on Twitch too, they are amazing (often giving top notch informal lessons)!

For the opening, following "opening principles" is enough for a beginner to intermediate chess player.
https://www.chess.com/blog/KeSetoKaiba/opening-principles-again
For improving the rest of the game that isn't the opening, I'd say mostly tactics and theoretical endgames would yield the most results for the least amount of time invested. When you begin to succeed with this, then you may slowly shift towards learning more advanced concepts, positional motifs and openings last. Openings aren't really of utmost importance for a chess player under 2000 rating (and maybe even for some higher than that it isn't too important).
If it is just the literal rules of the game you are after (like @OpieLovesChess asks), then here is a good resource to begin with:
https://www.chess.com/learn-how-to-play-chess
What should I study first?