you need a host and every client needs his own instalation of the software you wish to use.
if the clients are on a seperate network, you can set up a router with vpn access (pfsense on an old pentium 4 pc or something) and use that as a proxy for all pc`s that are running behind it.
you basicly enter the network trough the router and have access to all connected devices without instals if you use remote desktop or putty or the likes.
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EDIT: do you want to use the vpn to acces the miners, or do you want the miners to acces the internet trough the vpn?
if you want to have the miners acces the internet trough the vpn the easiest way is to connect the router to the vpn and have all traffic run trough the tunnel.
hope this makes sence.
either or. I have a private VPN software i use so i am assuming the most user friendly approach would be to just install the software on all 3 of my miners and just run it from there.
preferably for the long term i would like to have my whole network run on a single VPN but i would need a user friendly training module/guide to do that. i am a windows user.