heyo, im in yr 9 applying for yr 10 and im also in a partial aswell I haven't personally done the hast before but I have read a lot abt it and I think I can answer a few of your questions.
Firstly, for resources, there are some but they honestly aren't very useful, I bought something called notes edu and it was the easiest stuff i ever saw, the hast would be 10x harder than these online websites that say they will prepare u for hast so I dont recommend it, I wasted 100 dollars aswell with it.
Secondly, for maths Im not sure whether they will test yr 11 but I feel like they would, so maybe just go through some year 11 topics and see if u can do some of them. But make sure your yr 10 maths knowledge is good. Oh and its more of both mathematical ability and problem solving. For the math and science, the science component rlly doesn't need to be studied, it is mainly math and just logical reasoning perhaps. Its like science icas if u have done that before, from what I have heard u dont need to study for the science part vigorously maybe just the basics and a little yr 11 if u can.
For writing yes, you will have to write and a creative AND a discursive.
Finally, for abstract reasoning it is basically figuring out patterns and is similar to general ability but it doesn't have any vocab type stuff in it. Its all just logic pretty much(even tho i hate abstract reasoning). Its basically like one of those job tests u do just search some up and do them to get used to it.
man its been forever since i was last here lol
