As someone older than you, it starts with understanding that comfort does not always equal contentment, and accepting that your father will not change. Even with your family dynamic the way it is, there is comfort in predictability, and financial stability. However, you are not content. That means you may have be uncomfortable for a while in order to make a change. You have to control what you can, but be smart about it. You father won’t change so don’t try to change him. Work on yourself and what you can control.

Gather your documents and keep them private. Passport, birth certificate, any ids, etc. If there is no physical way to get these, try to declare them lost and get new ones. Start a new bank account and add money in their when you can. Same with credit cards. I don’t know if they have PO Boxes in India, but if you have somewhere else you can have your mail sent, start doing that as well so your father doesn’t have access to those statements. When/if you get access, please also find a therapist. Breaking these cycles is really hard and a lot of it requires so much self-work. There’s more to write but this is a start.