The title it’s choosen to have cpanel word in it because changing ssl port from 443 to something else directly in http.conf will bring trouble when you create a new account for instance (cpanel rebuilds http.conf automatically)

so keeping things short go to /var/cpanel and:

sudo vi cpanel.config

change apache_ssl_port=0.0.0.0:443 to apache_ssl_port=0.0.0.0:new_port
then:

sudo /usr/local/cpanel/whostmgr/bin/whostmgr2 --updatetweaksettings