it should be the same belt for all your machines. The never cf moto's use cvtech clutch so if you want to know how the clutch works you should find some videos on cv tech clutches (not you specific but al cvtech trailblock clutches are very simular.
on my 520/500s i use a ultimax belt (Ultimax Part Number(s)UA483).
A cf moto 500s you can change the belt using this method
t=249s
it's pretty tight but it can be done. On your secondary it's m6 insted of m8. Only one of the holes is threaded, on my machine i have threaded both holes.
Hpw often your belt needs to be replaced depends on your riding ( I got about 8000km of the oroginal belt until it reched service limit 33,5mm. On my last ultimax i got 10000km before it blew up. then i pot pn a moose belt (total garbage) only lasted like 2000km and know i have an ultimax belt again. I do drive much on the road so don't expectthat belt life in a mud hole. Inspect ypur belt somethimes and use compressed air to blow out dust from the cvt once in a while. On mine there was a "sticker" that told me to inspect the belt at 3500km and replace if necesary.