how do I supposed to pass algebra 1 if I didn't do 8th grade united states

Study hard and pay attention in class.

Talk to your counselor about this issue. There may be a pre-algerbra class you can take or get some tutoring. If you immigrated to the USA you are often placed with your age group regardless of your previous schooling. Most HIgh School will not place you in a class knowing that you could not pass, intentionally

And unless english is a hard language for you, and this is the first algebraic class, you merely pay attention, since there is really nothing in other math that gets you ready for it