@Anu7035 Oh dear - It may be a bit late to ask now as actually you might need planning permission, will almost certainly need building regs as well PLUS a fire risk assessment for short term rental (STR) that usually means fire protective measures in excess of what are needed for normal long term rental.
You will also need an insurance policy that allows STR and possible the permission of your mortgage company if you have one.
I am assuming you are in England by the way!