How to set up mikrotik to receive internet through a vpn tunnel from the central office?

Question

ZyXEL

Is available:
1 Central office in which zyxel usg 300 is configured as a vpn concentrator.
2 There are remote offices.
The Internet is available only in the central office, not in the remote ones.
All offices are connected via VPN to the central one. The Internet is distributed through a vpn tunnel from zyxel.
In one office, there is mikrotik in the rest, zyxel usg 40.
Zyxel tuned in simply, the LAN works, the Internet works, but the office in which mikrotik is located cannot be defeated. The network works, but there is no Internet.
How to specify mikrotik to go to the Internet through a vpn tunnel with the central office.
Zyxel configured through Policy Route.
It doesn't work with Mikrotik.

Answer 1

where is the config?
and so ip route add gateway=VPN