This is How to Disconnect Websites on MetaMask:
1. login to your metamask account.
2. click the three dots.
3. go to connected sites.
4. disconnect all websites.
This is How to Revoke Permissions on MetaMask:
1. go to:
2. connect your metamask.
3. click the revoke button.
4. pay the fee and confirm.
to disable the limit spending amount it will cost you money so just create a new wallet and move all your assets there and never connect it to any website.