confused with American education system

What is the difference between community college and university?
If it true the credit from community college can be admitted by university?
and about the tuition ,it is true there is a big gap between GC students and foreign students?

Actually, I am thinking maybe I should go to university to take some course improve my English, surely, improving my English is just the first step, what I really want to do is get a degree here.

Do anyone have any good suggestion for me, please?I really think the American education system made me confused.

Thanks in advance.

A community college is usually a two year post-secondary liberal arts institution, which means you are getting a general education instead of majoring in say, physics.
Credits are transferrable only if they are equivalent.  Either you get a credit or get exempted from certain pre-requisites as a results of having taken the required course.  E.g. you would not get a Physics 101 at university (a calculus based course), for College Physics 101, a largely non-Calculus based course. However, Calculus 101 may be the same for both and your college credit would be accepted.

Thanks TheYeti3
Things will be eaiser if my English as good as yours, even half of yours
Actually I dont have many options unless I change my major.
My chance is so slim, isnt it?