never too late to start imo
those games are really challenging, but very fair and have excellent controls. plus youll be jamming hard to the music the whole time and it makes you wanna beat it.
seems silly that a game with only ~ a dozen levels could have that much replayability, but everyone i know who is into MM has been playing em for decades, and theyre still a blast to run through
if you wanna try, start with MM2 on normal mode. its the easiest by far imo. and also the one that everyone else says has the best music to be fair it is '''REALLY''' good
if you get really stuck, then look up the recommended boss order/boss weaknesses