How to set up internet over a VPN connection?

Question

VPN

A Windows server with KERIO is installed on the company, and through it all users of the local network access the Internet.
But there are laptops that periodically travel outside the company and access the Internet via 3G-we can.
1. How to properly deploy a VPN on a server?
2. How can I access the Internet through our VPN server.
3. Add access to network drives via VPN.
4. Leave the Internet access on the PC only through the VPN connection and the Ethernet port?
PS Help, whoever can, links to literature, videos, etc. are welcome)))

Answer 1

Technical specifications are not accepted for free :) Voice the budget that you agree to pay for the work - maybe someone will agree
(I don’t write - I don’t like Windows, I don’t know and I don’t want to know kerio)

Answer 2

What you need: a white IP to which remote users will connect (or DynDNS, but that's another story).
Setup manual: at least here
Regarding Internet access via VPN: you need to leave on the client a route with the gateway of your VPN server (local VPN address) of the form: route ADD 0.0.0.0 MASK 0.0.0.0 VPN_client_address. By doing this, you send all the traffic coming from the remote machine to the VPN server, which actually cleans it up - both to the Internet and to the local network.
I won’t say specifically about KERIO, because I myself use Mikrotik.