"You've played 1 / 37 games" "Your avg rating 1.00" i've never been prouder

What a nice concept for a list! Surprised no one mentioned it yet but for 3D Mario, I think you can't find a better entry point than the most recent Super Mario Odyssey. I think it's got all the great things about the series wrapped up into one package, and its gimmick is probably the most user friendly of all the games. SM64 is also great but its camera controls might be a bit off-putting if its your first entry. Odyssey is very beginner friendly while also allowing for plenty of expression of movement for players once they get the core concept down. (It was also my first 3D Mario game, so maybe I'm biased.)