I will share here how to use Cloudflare Origin certificate (to use strict SSL) with Ubuntu and OLS
from SSH command prompt
1 - Create the certificate files
sudo touch /usr/local/lsws/conf/website.key
sudo touch /usr/local/lsws/conf/website.crt
2- Edit the files and paste the the certificate...
in AWS I allow access to https ports only from cloudflare IP list and it works perfectly. I dont think its a good idea to block access at the OLS level. either your host firewall gateway (AWS Security rules) or at the server level like UFW