VPN mikrotik and 3g modem?

Question

VPN

We have 2 Mikrotiks, both 951. The first (let's say A) is connected to the provider via ithernet and has a static ip address, the second (B) is connected to the Internet via a 3g modem, there is a VPN tunnel between them, the network works with a bang, packets go, networks are visible, but how to forward port 80 to the machine (192.168.89.253) from the network of router B so that it can be seen from anywhere in the country through router A (since it has a static ip). How to set up NAT correctly? I am attaching the diagram.

Answer 1

ip firewall nat add chain=dstnat action=dst-nat to-addresses=192.168.89.253 to-ports=80 protocol=tcp in-interface="inet" dst-port=80
on router "A"
tried like this
where "inet "your interface with a white IP

Answer 2

he is

Answer 3

On router A, we do dst-nat as mentioned above. And on the second, you need to make chains in the firewall -> mangle:
And in Rutes, register the route to the first microtic with the desired routing brand:
In theory, that's it. Now I checked this scheme, everything works.