Speed Distance Time | Test
Practice all of the SDT and Fuel calculations a lot. They might be in there, they might not. Depends on the questions you get. If you want to be an ATCO you'll need to be able to do the relevant maths, so it's worth practicing now. Nobody on here will tell you explicitly whats in the tests at stage one, but I will tell you that there is a chance that these questions could be asked. Learn about NM, altitudes, FLs, and SDT/Fuel calculations. If it doesn't come up you'll know it already for when it becomes important. The vast majority of people go into the tests not knowing what to expect, and a fair number pass, so it isn't impossible!