Obtaining HTTPS certificate using certbot

Assuming you have set up your VM and it is succesfully serving a website as a reverse proxy on a domain name, you can install certbot on your VM to easily set up a HTTPS authentication.

On a sudo-user, run:

sudo apt install certbot python3-certbot-apache
sudo certbot --apache

Go through the the wizard and enter the information. After it is done, you can update your domain name in the browser, which should now have a HTTPS certificate.