Hi TabUk.
Please have a look a the Capital Gains Tax sections of the government website here:
Capital Gains Tax
There is a capital gains calculator to help you work out your gain.
The help sheet HS283 will advise you how to work out if you are entitled to private residence relief.
HS283 Private Residence Relief (2024).
At the end of the capital gains calculator, is a link for you to register for a capital gains acccount, so that you can report and pay the Capital Gains Tax.