Somebody already mentioned what I consider to be the best resource, chess.com. Not only can you play online there but they have videos, puzzles, tutorials etc. from never played chess probably up to about 1800 rated player (a strong club member, somebody who does tournaments).
There is also a great mobile app, maybe computer too, called Learn Chess with Dr. Wolf that is also particularly good from the standpoint you can play games vs the computer and it tells you why some moves are good or bad.
Once you've familiarized yourself with the rules (using chess.com tutorials or the YouTubes) and played each other if you want to get better I'd suggest something a bit counterintuitive: learn to get better by learning Chess in reverse.
Practice end game scenarios. Start as simple as mate with a queen and king vs king, rook and king vs king, pawn and king vs king, etc. and then move onto more positions. Looking up online endgame tactics or puzzles to help.
Then look at chess tactics. Again Chess.com has this, but you can start at
https://www.chesstactics.org/ and after that move onto another website chesstempo.
Once you've mastered those then, and only then, start looking at chess openings. Most people want to jump into learning openings, but unless you are just interested in memorizing lines / moves doing so isn't going to help much unless you have some good fundamentals under your belt and can appreciate why the moves are being made.
Edit: Also consider Go (Baduk) as another game. Completely different than Chess but an ancient strategy game for 2 people that is easy to learn but hard to master. I learned chess my senior year in high school by hapenstance being in the library when the club met and was rated just under 2,000 a year later. However Go still eludes me. I swear it is a different way of thinking.
And of course modern boardgames are a lot of fun, check out boardgamegeeks.com for some good 2 player option ones.
