How to implement a simple corporate network?

Question

Active Directory

Actually I'm asking for help, I don't have much experience in building a corporate network, so little things ....
Actually there are 5 stores and 15 computers, the stores are all in different places with their own Internet. It is necessary to organize access to a shared disk that is on a server (WIN SERVER 2013) + connect printers + in the future intranet + access to cameras, etc.
The scheme that is now something like this: How, how to tie everyone together? All computers must go to the Internet through their own channel .... The same question, if AD is created, how will computers in another room with a different Internet find the domain ?!

Answer 1

routers are simpler on points. one is more powerful on the main. connect all vpn. and we distribute one dns server to all clients via dhcp). it is possible (or necessary) even through nat

Answer 2

"man vpn, Luke!" Read what VPN is in general, and its specific implementations, in particular (for example, IPSec, OpenVPN, L2TP protocols). Read about the miraculous pieces of hardware from the miraculous manufacturer Mikrotik - they support all of the above, and many other useful protocols.