Connecting two wireless modem/routers that are far apart together

[IT Lady]

Hello, I have two wireless modem/routers - a Ugo Mach5 CN458 and a Swift 4G - in two branches of my company that are distance apart and i want to connect them together so that they can be on the same network and workers in both branches can communicate and share files. How do i go about this?

 

[Emerald]

elaborate on "distance apart"

 

[Emerald]

you are most likely looking at setting up a VPN