Unless you provide details of complete terms and condition it is difficult to arrive on a conclusion.
Here you should consider whether Bookings.com is merely an agent booking on your behalf or pay you rent fixed each month.
As you are using your premises commercially, GST is to be paid. However you need to consider limit of Rs. 20 lakhs in a year for GST registration.
Further if arrangement is not that of agent then GST is to be paid by Bookings.com
Providing a little more details of full transaction cycle will help answer the question with complete solution from different angles.