How to use the IP Blocker in cPanel?
1) Log in to C Panel.
2) Click on “IP Address Deny Manager”
3) Enter an IP address or range you would like to block, then click "Add"
That's it! You have now blocked anyone using the IP address which you have specified from accessing your website.
You can also see which IP addresses are currently being blocked.
... and you can remove IP blocks by clicking on “Remove IP”