Pleeeeeeeeaaaassseee help me out :( You can really change my future here :(?

I am 12 and currently living in southeast asia. I REALLY want to go to a boarding school in england. I hate it here sooo much. You can't do anything. The only sports they offer here are soccer, basketball, swimming, tennis and track which I hate so much. I want to go to cambridge university as well so I figured going to a boarding school there would benefit my studies as well. I know it's really expensive, but I am pretty bright and I am willing to do anything to get in so I figured maybe I can get a scholarship ( but honestly, my parents are wealthy enough to pay, money is just a dumb reason to not let me go). I fight woth my siblings a lot, but i never fight back and the one that gets hurt and blamed all the time, even my sister who's 4 years younger than me calls me a *****. My parents won't let me go because they will miss me.. What should I do? I've made up a list of pros and cons, I've got 40 pros and 4 cons so far ( is that good enough?) but I'm afraid of giving it to them. And even if my parent's let me, how do i apply? Do i need a permanent resident card? A visa? And where do I have to go on the holidays? What's the students like? I'm going to the 7th grade after the holidays and hoping I can go to the boarding school in year 9. So I'll have to skip half of 8th grade,right? Here, schools start from july to june.