Help with setting up SSL remote access

First i will tell you my setup. I have mu HA running in my IoT VLAN which connects to a cisco switche and then to a cisco 5506 firewall. The firewall provides the VDLSL link to the internet and is setup with 3 sub interfaces for Main Network, Kids Network and IoT. All my IoT devices sit in the IoT VLAN including HA. I also have a web hosting resseler account. What i have done so far is setup a sub domain to my main web page so home.webpage.co.uk which i have put an A record in the DNS for it to point to my external IP address (Which is a static IP) i have then forwarded the portsa on my firewall to HA so if i type http://home.webpage.co.uk:8123 i get the login screen to HA. Now i know this is not secure and i have not logged into it this was so i need to get the ssl section setup where i am getting a bit confused with. I do get free SSL certificates with my domain name so i have activated that on the sub domain mentioned above but it will not access HA this way. Any ideas guys?

Managed to sort this now with the help of cloudflare