You need to pick a machine (if you only have 1 you don't lol) to be your web portal, bang a block of code in via ssh or command line (I copy pasted) then you can access Portainer via the web portal.
From there "Stacks" is Docker Compose and you can fiddle with your containers, networking settings and all the other stuff via a UI instead of having to SSH in all the time to look at your compose files.
Then if you wanna use docker on more machines you just bang a block of code into that machine via ssh and it will appear in your Portainer
Far easier imho
"Dodgy Firestick"