[Kizzy]

Are you working? If you are I would try my best to reconcile with your dad, I know it's hard. I live with my son and getting used to a different dynamic as 2 working adults sharing a space other than in your case father and son is hard.

However even if it is your home it is still your dad's house and you have to appreciate that, you mentioned decorating if you had a private rental you would not be allowed to redecorate.. even putting pictures up have to be done so there is no damage at all to the paintwork on the wall.

In your dad's house you could ask to make changes to your room but offer to put it back to your dad's liking when you eventually do move away. Even though it doesn't seem like it this is the best option staying at home, but you have to make compromises and be mutually respectful, just as you would if you had any housemate.

Make some rules and stick to them, things like housework, washing, loud music, contributing to food and bills.
Ask your dad to reconsider if you are willing to make some changes.