I'm trying to say this in the most respectful way possible Ahad, but I think you could improve your English a bit.. (Unless you are just typing fast on the forums, which is a different story).
If you struggle with English, I have a few tips that may help:
1) Read lots of books. Try to make sure these books are written with in a way that it will expand your vocabulary (what I do is open the book to a random page and then see if there is at least two words I don't understand or can't define). Make sure you are interested in the books, this will make the reading much more enjoyable - when I was nine I was reading about two books (~300 pages) per day. By doing so you will 'accidentally' become more fluent in writing (no, it won't happen in one day, it takes time,) and you will expand your vocabulary. The best thing to do while reading if you really want to take the learning experience as far as it will go is to have a dictionary beside that you can use to look up words you don't understand. Books I'd recommend are; The Lost Symbol by Dan Brown; The Casual Vacancy by J.K. Rowling; The Kite Runner by Khaled Hosseini; Wild Cat Falling by Mudrooroo; The Harry Potter Series and finally the Percy Jackson series.
2) Make a list of words you'd like to learn or commonly mispell and put them up on your bathroom wall or something.
3) Try reading some of the high-scoring reponses on ATARNotes, although they may be a bit off topic and sat under different conditions than the MHS exam, they are still very fluent.
For math, I'd say practise is key and the more you do, the better.
Maybe try doing some intermediate past AMC papers (found here:
http://ec-web.elthamcollege.vic.edu.au/snrlibrary/resources/subjects/maths/PastComps/maths.htm ) and try to understand the answers you got wrong and how you should have gone about solving the problems. Also, if you are bored and want to go really overbored with your math, it might be worth trying
https://mathfights.com . Also just revise all the stuff you know so far.
But, as mentioned by other people on this thread, acedemia is not the only critria that is looked at during year ten MHS selections, so you are going to want to be a good all rounder. I'd suggest taking up an instrument, doing some volunteer work, taking a first-aid course (if that interests you), keeping up your football, doing other co-curricular subjects (i.e. chess, swimming, debating [which also help with reasoning and writing] and so on...), and, of course, volunteer work.
If you get to the interview stage, be prepared for they're questions (i.e. why do you want to come to MH? how will you help the school? what makes stand out from the next person?) also, try to be modest, polite and well dressed.
Finally, I'd recommend you make this a learning experience - take this as an opportunity to become better at academics, learn new skills, learn how to handle an interview and learn how to have fun at the same time.
Hope I helped
