Firstly you need a VPS/Dedicated server where you have access to the firewall configuration. There is plenty of articles out there to describe how to implement this and it will vary depending on the server, if you have CSF on the server just google CSF deny all but cloudflare.
Basically you are going to whitelist/ignore cloudflare IP's which is step they suggest doing anyway. From there you just deny all other traffic to those ports.If you are using CSF for example:
Code: Select all
tcp|in|d=443|s=0.0.0.0/0 # do not delete tcp|in|d=80|s=0.0.0.0/0 # do not delete