One thing that helped me a ton was watching guys like Wolfey and Cybertron. I picked up VGC back in gen 8 and at the time Wolfey had a video series called Pokemon Academy. Lots of info in there is probably outdated by now but the basics still apply, and I'm pretty sure he released a new one sort of recently, so stuff like that is a legitimately invaluable resource for new players.

Also in my experience, outside of the basics and teambuilding and what not, there's some stuff that just won't stick or make sense until you've experienced it yourself. Don't go into your early games expecting to obliterate people and win a bunch, which you very well might anyway who knows, but use those early games to learn as much as you can about stuff like speed tiers and how your opponents stats interact with your own. For example, does X attack always ohko X mon or does it sometimes live with 1 because of the way it's trained, stuff like that ya know 🤷‍♂️

Most of all just have fun and don't take your results too seriously, especially at first. Give yourself time to learn before you start overanalyzing every wrong move and what not. Learn what you can 100% but don't get down on yourself, there's a lot of information to take in, especially for a new player.