GOautodial Open Source Omni-channel Contact Center Suite

Hello, i have posted something here and i think i got a reply but i am unable to find the post again. I have installed goautodial 4.0 from scratch again and followed the instructions on this page : https://goautodial.org/projects/goautodialce/wiki/Goautodial_Getting_Started_Guidev4

Except that there is no mention of an ssl certification to be installed there. Now I have fuly configured the server and i have 10 people calling in outbound. I have 10 from another country wishing to log in and make calls. To access the server, they type in my public fixed ip address and on the router (Mikrotik) i have configured the NAT setting to redirect to my server internal IP. Basically the server is on 192.168.60.180 and my public IP redirects to it. I installed Goautodial 2.0 and that worked for some time but since this is not supported for upgrade I decided to replace the 2.0 by the version 4.0. Now people outside my network are able to connect on the server (Login with username and password) but also register there SIP account on eyebeam or Zoiper but within the browser when they click on Login_to_phone button, nothing happens. THe phone doest ring also.

I have been asked to put SSL on the server but i am a bit lost here. Should I follow steps mentionned here : https://goautodial.org/boards/3/topics/19122

I even searched what is an FDQN and i dont have one so my public IP is the only way to access my server.

Can anyone help please?