my question:

-how many skills can be enchanted to its max?
-can pasive skill enchanted?

depends on ur server...
after kamael or hellbound u can enchant 3rd prof and passive ones
before interlude only some from 2nd class
max enchant is +20 and there is no limit for enchanted skills, but every new skills/fail needs another BoG, which can be obtained....... SEARCH.

on offie (gracia but since hellbound it work like the same) you can enchant pre 75 skills to +30 and 3rd profession skills to +15
passive skills can be enchanted too
not all skills are enchantable, you can serach wich skills are enchantable with google.

each enchant have a chance to fail, more you enchant, less chance you have to success
all skills enchant cost XP/SP
if you fail to enchant, you lose all your enchant
for exemple, yo try to enchant trance +5 to +6 (it cost 599 000 SP and 5990 000 XP), if you fail, u'll have trance +0
there exist some book to prevent the lost of it
it's oblivion codex
u can buy it from suspicious merchant with epaulettes and adenas.

one of theses book can be used to make "safe enchantment", it cost 3 times more xp/sp
another book is used to "change route" of the enchant skills
for exemple, you have enchanted trance for cost, u can change the route to trance for chance with the book

the 3rd one is used to get xp/sp back from skills enchanted but u don't get the totality of xp/sp spend back.

really nice information dude

hoaaa...thx for the info man.....