4 tests for year 10 maths? Wow, that's a lot. At my school we had an online test (I did year 10 in 2020), then an assignment, and then 2 in-person tests.
The good news for you is that schools generally put a greater weighting on the tests later in the year, particularly if one of them is a yearly exam, so you still have time to pull yourself up. I would recommend you learn ahead of your class then do a lot of thsc past papers. Particularly do the papers from 2018 onwards as this will be most relevant to your current syllabus. Doing past papers under timed conditions helped me go from an average of low 80s to getting high 90s and close to the top ranks from the second half of year 10 onwards.
Don't worry too much about the final mark and just focus on improving for the next assessments. And make sure you redo all the questions that you got wrong in that first test.