Securtity

in order to link the website to Cloudflare and keep the emails working we need to add these DNSs into the Cloudfalre

First record : 

Recrord Type = A

Name = mail

Content = {Cpanel Server IP}

Second Record 

Recrord Type = MX

Name = example.com

Content = mail.example.com

in this case your email from webemail will be working as expected 

some times when you want to share a link on facebook and your website is protected by Cloudflare you will have this error 

"access denied used cloudflare to restrict access"

to solve it you have to "Whitelist Facebook ASN IP in Cloudflare"

So now how you will Whitelist Facebook ASN IP in Cloudflare, to do it follow the below steps 

you can whitelist Facebook’s entire IP range in Cloudflare’s Firewall settings.