help (pls)

I’m an intl kid and I decided self-study AP Psych because tutoring costs a bomb. I signed up for tests and reviews with an institute but I’m getting 40s out of a 60 point unit wise quiz on almost every one I take. I get decent on the FRQs TOUCHWOOD. Need help w the scoring. What is an estimate albeit safe percentage to land up in which will grant me a 5? I don’t know anything about your weighted/unweighted grading system so explain it to me like you would to a 5 year old.