I honestly just need some advice So...

Ok I original live in the U.S Florida but my patents are UK citizens and you know trump and all that but anyways we had to move to the UK and in Florida I was in 8th grade in middle school and school had just started so I just started the 8th grade I wasn't in school long enough to make a month anyways I moved to UK and got put in year 9 and I now have a big science test coming up that's suppose to sum up year 7 year 8 and year 9 work and school in Florida is super easy compared to school here anyways I have 13 days to study for the test and I'm trying to but I can't memorize all the stuff and I was wondering if any of you have some tips and tricks to help me study or if you recommend any studying apps I would really appreciate it I'm literally in my room about to cry because I'm so tried and stressed out pls help me