Cross roblox game communication

I know this has been asked before but the answers were very vague so I ask anyone willing to respond to be somewhat clear and elaborate with their reply. My dilemma is that i wish to sustain occasional information exchange between two independent Roblox experiences. I’ve seen the other replies to questions similar to this and all they said was to use Httpservice however I’ve reached a difficult point in the process. So what I was hoping to do was have an external party in which both games can access to allow information exchange between the two games via :GetAsync() and :PostAsync() but my problem is that i have no idea how to get ahold of a external party that can facilitate this communication. This is why i need a specified answer as to how to use httpservice for communication especially how to use :PostAsync() to put information on said external party. Please prompt me if you need any extra info regarding the matter and thank you for your consideration

You could try to use Messaging Service but I’m not 100% sure this is effective. There are also some plugins out there that allow you to do so.