Help me outfit my almost 2 year old.

Wife and I were talking and agreed we want to start “teaching” my almost 2 year old. I found a “cheap” Burton after school special in 80cm local. Is 80 a good size or should I look for a 90? I don’t see toddler snowboard boots in her size, she wears a size 5 shoe in toddler. Can I just use regular snowboots for now?

Any helmet recommendations? What brand board or does it even matter?

Lastly but not least, any good tips as far as reaching a kid that young? I figure I’ll just drag her around for quite some time but I honestly don’t know how to teach her.