what are the main things i need to know in algebra II
the topics named in the table of contents, eh?
If you don't have a textbook, you can
(a) go buy one cheap at a used-books store
(b) use google. There are many web sites where such coursework can be found
(c) go to a nearby high school and ask a teacher there to discuss the subject
Algebra 2 covers a wide variety of topics, so if you're looking to study ahead, that's a good idea.