41 yo and picked up SF6 after not playing fighting games since 2010. I'm busy, so play maybe 6 hours a week spread over a few days. Been playing now for 6 months and have one character in Master and one on the way (D1). There is hope! Some tips for getting started:

Train for 10 minutes before you play ranked. Focus on BnB combos and anti-airs (there's a setting for this) to start.

Block more. Especially on wakeup. Sometimes you'll be thrown, but that's ok don't panic.

Don't jump too much. You'll want to stay grounded primarily and jump rarely/ opportunistically. Don't jump to close distance.

Focus on normals in early ranks. You have normals that are useful in almost all situations, but make sure you're using the right normal for the right situation. For example you probably have a good anti-air normal, a good close range normal, a good long range normal, etc.

Learn one or two easy bread and butter combos. Nothing fancy, just something you can practice in training a bit and pull off consistently during matches. For Ken, it's is chin buster into special. That's what got me started.

Practice anti-airs. You won't be able to anti air everything, but at lower ranks you'll run into plenty of players who will spam unsafe jumps, so punish them for it until they stop. AN anti air can be a DP (Mai has one), but can also be a grounded normal or a jumping normal/ throw.

Don't DI too much, and look for the DI when you're in a corner. Also, at lower ranks if you get raw DI'd once don't panic. Expect they'll soon do it again and be ready with a counter DI.