Are adoptive parents allowed change child's religion?

It is nice to hear that you have got adoptive parents. Please note there are many children who do not have parents, you are one of the lucky children who have at least adoptive parents. Adoptive parents have the same kind of responsibilities as real parents. Sometimes we as children do not like the decisions of our parents. If you are 15 years of age then you would need to abide by your parents wishes, unless you have a compelling reason why you should not. Even if that is the case you would need to talk to your parents. The question regarding religion would have been discussed initially when the child was adopted. When children are put into adoption generally they tend to put the child in the same religion as they were from. Sometimes if a match is not found then a child is given to a caring family who will give them good family values. I would not worry about this.

Anyway I am not allowed to practice my Christian religion in their home, only Sikhism

Iam very much pleased with d ans given by Sri KS Johal- a mature n parenting advice. Robert u shd be greatful to ur Sichk family instead of trying for ways to question them. Call them Mom n Dad live like a true son of them forgetting that they are adoptive for if not fir their genorosity where would u have been after ur mothers death?. At the age of 9 only u r questioning ur brought up parents on religion is very bad n would be ungreatful my boy. Love them obey them n u can find ur own path after u grow big. .

My adoptive parents told me I am ungrafeful