Virtual Host, Lets Encrypt, Reverse Proxy all in on

virtual host:

https://www.ostechnix.com/configure-apache-virtual-hosts-ubuntu-part-1/

reverse proxy:

https://www.digitalocean.com/community/tutorials/how-to-use-apache-http-server-as-reverse-proxy-using-mod_proxy-extension

lets encrypt:

https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-18-04