Dear aspirant,

As you have mentioned that you don't have domicile certificate and taking into consideration that you want to fill the admission form of certain entrance so let me tell you that kindly mention in the comment box the name of the application form which you want to fill because only then I will be able to guide you in a better manner.

In general case I would say apply for domicile certificate if not applied ,you would get it in 10-15 days(if time is there).