Pixel streaming with matchmaker

Hello, I want to set up a project under ue4 including pixel streaming with the matchmaker system allowing multiple instances to run on a server.

Currently I use my personnal pc as a server with open internet (not local) but eventually I would like to put a dedicated machine.

So far I only managed to set up the pixel streaming in the open internet, and with only one instance. So my questions are, how can I go set up the matchmaker system including multiple instances on the same machine?

Once the server streaming pixel is started. How can I make sure that when a user goes to the site, the ue4 instance launches by itself?

Because currently the web page bug if ue4 is not started. And then I would expand the experience, but I would first like to understand how it works, so as to put a proof of concept in place.

Thank you very much for all the information that could help me.