So when I try to use it from the cPanel it says a variation of this email already exists.
And when I try to use it directly from Cloudflare it works, but after a few days it says that you have to remove the epizy nameservers or your site will not use Cloudflare
Other Information
I can’t use cloudflare, and it’s making my site slow
Never do this. Because you had this enabled at some point, it way have messed up Cloudflare and parts of the control panel may not work again on that account.
Because Cloudflare needs Cloudflare nameservers. Once you set Cloudflare up, you cannot remove Cloudflares nameservers.