Make Corrections in Property Booking Site and Add Payment Gateway Integration

HI I want to make corrections in the following project whose flow as follows : a property booking portal where each day 4 to 5 slots will be available say 7-10 ,11-13, 14-17, 18-21, 22-00 hrs. each slot will have certain fees. all the slots and fees will be set by admin in the admin panel for each slot and type of event. Also he should be able to create security deposit for the slot and event type. Secondly a user panel to login and check whether for his preferred date slot is available, then he will select the slot and make the payment accordingly. He must be shown detailed terms and conditions and once he accepts the tnc then he proceed for booking payment. at the time of user creation an email otp verification has to be done for the future correspondence on email. email has to be unique. User must have right to cancel the event . once he cancels his name should reflect in cancellation list at admin panel and user should be able to see the booking in cancelled section. admin can cancel any booking from his id. as well as admin can create booking for any slot w/o making payments. admin should able to see all the cancelled bookings as well as completed booking in one window for creating refunds via payment gateway. admin should able to generate list of refunds to process, once refund iniated, he should be able to see the status of refund. Note. on index page there should be a calendar view which I will share which will show the booking status. Now I am attaching the existing project code here In which all the developments are done only some small corrections and payment gateway integration is pending and return payment is pending. I want you to put this code on a dummy cloud server so that we can discuss the further corrections and payment gateway work. estimated time line is 2 days.