I got rejected from sixth form, but I have the grades I need to get in!

They want a pass/C for the subject that you wish to do at A-Levels and they also said that a D in maths is not a problem but I would have to resit it in sixth form which I am very happy doing, and 3 of friends got the exact same grades as me but they had a E in English and Maths and they got accepted but they are British. I also need my A-Levels to go to university.

I was born and raised in England and I can also speak fluent turkish and english, but I think its because I told my school that I want to do loads of work experience in sixth form and I REALLY MEAN LOADS!, the school doesn't even bother with my work experience but they do it for other people, so I went and arranged it my self which I am starting tomorrow at a care home with people who have dementia and the manager said to me that the school should arrange this because I am young and that something could happen to me and I said they don't help me with anything and he said that you would normally have to be 17 to do it at a care home which an elderly person with special needs but he let me do it because I am determined and he now knows that the school won't help.

Perhaps they did better at interview? I highly doubt it's anything to do with being British or not.
Again, I'll question your desire to do A levels/ go to university with your academic record, but it's up to you what you want to do with your life...

Why don't you consider doing an A level in Turkish? You're almost guaranteed to do well, and it gives you a proper qualification to say that you are fluent in the language.
If you had a rage at your school/ sixth form in your interview about how useless they are when it comes to arranging work experience, that wouldn't have helped. No other secondary school that I know helps arrange work experience properly (except 'here'a a "useful" website, go have a look' when it came to the obligatory 2 weeks work experience in year 10). At sixth form, there's a little bit more help - they'll look through application forms and give advice, particularly for those students who need work experience as part of their courses. You can't expect them to arrange it for you, perhaps the other students you claim are being given all this help at your current school are actually asking for help and going to the careers adviser with a completed application form for them to check through.
Also, bear in mind that doing too much work experience may affect your academic performance. Don't arrange for every free hour to be spent doing work experience. When it comes to university applications, they are less interested in the quantity of work experience, but what you have learnt from it.
The age limit is something to do with health and safety, I wasn't even allowed to volunteer in a charity shop until age 17! What was I going to do, stab someone with a coat hanger!

Hi, basically to I should have had my sixth form interview but I didn't and everyone else did in my year

It's likely that they just haven't gotten to you yet, the interview process can take longer than you think. They might time the interviews based on alphabetical order, do either of your names begin with late-alphabet letters? They could also time the interviews chronologically based on when you applied to the sixth form, was your application generally later or earlier than others? Also, this sixth form could have had loads of applicants and interviews take a lot of time!

So don't jump to conclusions, there are many reasons why you will eventually be interviewed and very little why you haven't gotten in.

Also, I'm pretty sure sixth forms aren't allowed to decline you until you receive all your grades. Don't quote me on that though.

In conclusion; don't worry. Unless you receive a letter from them specifically saying you haven't gotten in you'll just have to wait, they can't just ignore you, that isn't professional. Good luck with your exams.