Changing WebMail URL

1. I've create subdomain = webmail.MYDOMAIN.tld (Working)

2. I've added it to DNS working (Working)

3. I've added Lets Encrypt Cert = webmail.MYDOMAIN.tld  (Working)

Now I would like to change = https://cpanel.MYDOMAIN.tld/etc/apps/webmail/
so everybody can acces it via https://webmail.MYDOMAIN.tld
How do I go about setting this up ?

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