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