Welcome back to Marvel! Get ready to want to simultaneously backhand it and make love to it.
A few things I would recommend...
-Don't be afraid to use the auto combo for a while. It jumps you into having some fun rather than just making you flail your limbs. If you do use them, pay attention to how your character's moves flow as you do. It can help you accustomed to the rythym of the magic series. But you will want to move on from them sooner than later.
-Play the story/some arcade runs. The story is cheesy and hell and generally bad, but it's also kind of awesome. Hard to explain, but it's enjoyable. It and arcade runs will also get you into the rythym of matches a bit and help you learn more about characters.
-Do some low level missions. Most of the low level missions will just be basic special moves and basic magic series combos. Good ways to ease yourself into systems.
-Take Ryu into the training mode. Practice hitting LP,LK,LP,HP,c.HP (launch and then follow them into the air) and do those commands again. Pretty much everything branches off from that.
-Use the tag system, ALOT. Start off by tagging into your 2nd character after that basic air combo I listed above and do the combo again with the 2nd character to extend it. Just like the magic series, use that as a base and go from there, and eventually you'll realize the possibilities that branch off of it.
- Beat the shit out of someone online in a way you probably didn't deserve and relish in it. Then lose in a way you probably didn't deserve and be salty about it. (Seriously though, don't be afraid to fuck with player matches and the beginner's leauge as you're learning. No better way to learn once you're in a match, but I recommend learning at least some fundamentals before going in)
-Scream "IT'S MAHVEL BABY" occasionally.
And you'll be good!