The following command line will change the default port VestaCP 8083 to 2083, you can change it as you wish, for example 65001 or 2087 and so on.
Open a terminal, connect SSH and run the following command:
sed -i 's/8083;/2083;/' /usr/local/vesta/nginx/conf/nginx.conf && v-add-firewall-rule ACCEPT 0.0.0.0/0 2083 TCP && service vesta restart
Do not forget to update all VestaCP packages, which should be done earlier before running the command to change the default Vesta control panel port.
Check, open control panel vesta with new port in setup.