I could successfully add DNS records at Cloudflare DNS table.
As my NS is of Cloudflare, It was not possible to control the MX records by my CPanel directly, so I needed to
My problem is that I can only create email users named:
[email protected]
Is there a way to use CPanel and Cloudflare and create users @rootdomain.com directly?
May I ask have you got NS type of DNS records at the DNS tab of Cloudflare dashboard for your domain name, or rather referring to the domain nameservers?
Correct.
Add an A mail and make sure it’s 
(DNS-only) as follows and also make sure your MX is pointed to that unproxied mail.domain.com hostname:
I have to admit, I never used [email protected] format, rather [email protected] for an mailbox user.
Yes.
Maybe the issue here is, your origin host / server is using domain.com instead of sub.domain.com for it’s hostname / rPTR record?
And the root domain (naked) is proxied 
?
My practice is to use separate e-mail provider, like for example Namecheap e-mail (one mailbox with up to 10 aliases) for the origin host / server where I host files.
Therefore, each of the domain names I add using, be it cPanel, ISPConfig, Plesk, has it’s own mail sub-domain used to send e-mails.
Below as images of both cloudflare and cpanel dns tables
Cloudflare
Sorry i was not allowed to post all images in one post
My name servers are of Cloudflare for the root domain (mydomain.com)
In Cloudflare I added: an A Record for mail.mydomain.com pointing to the cpanel IP.
All my mail/mx records are not proxied
I added photos in the other replies for your to kindly check them.
Do you mean that they receive [email protected] but on the server of the mail server pointed as “mail.mydomain.com”? Because this is what I need.
Most people use the @rootdomain mail format, and cPanel supports this. Your DNS records here are properly configured for that domain. If your host doesn’t let you create a @rootdomain address, you will have to ask them why.
Not that. Standard configuration is to have a ‘mail’ hostname so email for @rootdomain follow the MX record and are delivered to the ‘mail’ server.
I could figure it out after watching a video showing an easy trick.
The steps are just leading me to have the correct DNS records without any effort as below:
I think we only need to now the proper mx records for cpanel.
It gets a little complicated when you are hosting your own server and already uses Cloudflare.
Your suggestion assumes that website is hosted on a service that already uses cpanel
Yes, the initial question was about the cPanel mail server, while having your own mail server on your VPS, is another complication that I don’t know of.
