there is a timer for it to change, but you can change it manually by holding kameo button after using it.

Drunken stance f3+4 (starting frames parry punches) Tiger stance f (pushing forward parries mids and punches) Crane stance auto low parries all lows (given you re not pressing any button) I might be missing something but thats some of them

It depends if you know nothing about him it takes very long and patient to learn him. Try to studying Lei videos and copy things, thats what I made back then and still do.