How to set up 2x Mikrotik from different branches of OpenVpn?

Question

openvpn

How to set up 2 Mikrotiks from different branches using OpenVpn , if Internet access is via zyxel in both cases (due to the fact that a yota + zyxel poe outdoor antenna was purchased) on this particular zyxel giga ii model,
therefore the zexel-mikrotik circuit -users in the office and the same at the branch
Essence of the question:

• Will OpenVPN work correctly if the server (ovpn) and client (ovpn) are transferred to mikrotiki? (white ip)
  

I found quite a few manuals, the only useful thing I found in the formulations of ipsec over nat-t,
but I did not find specific instructions and sequences

Answer 1

leave zyxel nat and set up everything on mikrotik. Everything works for us.

Answer 2

how will the mikrotik client connect exactly to the mikrotik server, do I need to create routes or something?