How to link computers on different subnets?

Question

Computer networks

I came across a network in which computers with IP, for example, 192.168.0.1, quietly interacted with a computer with IP 10.5.0.10, and both, in turn, worked with a server with IP 192.168.5.215. The question is what needs to be done to get such a result? In a normal locale, the computer 192.168.0.1 will not be able to ping or interact with any 192.168.88.10.

Answer 1

configure routing on network routers.
Let's go and read "nets for the little ones"

Answer 2

Install a router?

Answer 3

It would be easier if you describe the structure of the network and say who you have as a router.

Answer 4

1) If the networks are physically separated, they have different providers.
Check VPN server.
Set up VPN connection on routers.
One of the VPN servers will be the main one (with real IP). Routers from other subnets will connect to it.
2) If the networks have a common provider and have access to a common
iptables router, try it. it seems to be sufficient to allow the circulation of packets between networks.
3) If the networks have a common provider and do not have access to a common router
Horror))) You need a VPN server with a real IP. and see point 1