So here is the answer to your question.
Firstly the nature of the property is a self acquired property which means your father has exclusive right, title and interest in the property and he can alienate, sell, transfer the property without obtaining any consent. from any family member.
Firstly, yes it is legally possible for your father to transfer the property in favour of one person (it could be anyone) by way of will. The will should be executed with free consent and there should not be any coercion/undue influence at the time of execution of the said will. Although you can informally and mutually settle down the terms within the family at the time when the will is being executed. And if no will is executed and you father dies intestate then all the members in the house including the sister and mother would get equal propionate in the said property.
Secondly, you can claim possession if you are incapable of earning, as through mutual understanding you can always ask for possession but there would be no right, title and interest in the property once the property is transferred though will. You should also know that one the will is executed, you brother doesn't have an immediate right over the property and he would only have the right title and interest over the property after the death of your father. So even if the will is executed and your father is alive, then the will can se set aside or a codicil to a will can be made during the lifetime of your father. If a will is executed transferring the property in favour of your brother, then the right of your brother would only accrue after the death of your father and till then you have the same rights in the property as every person in the family. The permanent address on your official documents can be changed by way of other relevant residential address proof such as sale deed of other property or rent or lease agreement etc.
I hope I have answered to all your queries, feel free to approach us again and we would be happy to help you.
Thanks and Regards
Varun Talwar, Advocate Delhi High Court.