this is the reason everybody trying to self-host a system must familiarize with at least basics of networking and computer technologies 101: Self-hosting information for beginners.
Talk, TURN, “Talk HPB” are different applications which in fact belong together and unfortunately AiO integrates them into one container hiding the real system architecture (but simplification is the goal of AiO) but CODE is definitely separated.
Running complicated things like VPN and reverse proxy in front of AiO definitely requires deeper understanding and will never work for a layman. If you want a turnkey solution choose a managed solution or maybe standard AIO without customization - otherwise learn how setup and especially troubleshoot and fix your setup. and one of the first learnings - even if some things are part of a bigger puzzle each part has different requirements. for me the drawing I saw shortly was a real eye-opener how complicated even such a simple thing like browsing an URL is:
well I was aware of all steps but never spend a second to put together how many moving parts are involved