For getting used to the game I actually recommend using YouTube. There are a ton of good videos with guides and information. Not currently recommending any specific channels but several top players from Melee and Sm4sh have been producing content with various degrees of usefulness.
In terms of a main, I would recommend giving
a shot, however if he was your main in Melee then perhaps not. I use
due to how incredibly fast he can feel. He's a very combo heavy character but keep in mind he's a projectile user so his playstyle might not suit you.
Whatever the case, best of luck!
Edit:
Some other characters you might want to try.
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