There’s a few online sources you can use that focus on AP CS questions, and as long as you’re studying nearly everyday, you should be able to get a handle on what the format for the actual AP test will be like, which is half the battle 
Here’s a few reliable websites to assist you!
http://www.learnerator.com/ap-computer-science
https://apstudent.collegeboard.org/apcourse/ap-computer-science-a/exam-practice
http://www.varsitytutors.com/ap_computer_science_a-practice-tests