1. Yes.
2. Yes exempted.
3. If the working women's hostel business is a separate and distinct business activity, then it is necessary for the GST-registered person to obtain a new GST registration for the new hostel business. If it is considered as an expansion of the current business, then it can be included in the current GST monthly return.
4. If the working women's hostel business is exempt from GST and RCM applies on rent payments, then input credit can be acquired through RCM but it can't be utilized for making GST exempt supplies, it can only be used to set off GST liability on taxable supplies.