HTTPS
From James's Wiki
The Certbot from the repos is old...there was some security issue that forced them to shut down something that the old version uses to create security certificates so it doesn't work anymore. the following instructions works around all that
sudo apt install letsencrypt
apt-get -t stretch-backports install certbot
sudo apt install python3-certbot-apache
the following is to get the certbot-auto script and get it running
wget https://dl.eff.org/certbot-auto
chmod a+x ./certbot-auto
./certbot-auto
NOTE: not sure if certbot-auto is working..
to add sites manually:
sudo certbot --apache -d example.org -d www.example.org