I've tried to find a solution to this, and hopefully it's something simple.
I am using Hetzner Cloud with their new Networks feature.
This means that the hypervisor assigns two NICs to a machine that belongs to a Network.
Nic 1 (ether1) is assigned a public IP address by DHCP.
Nic 2 (ether2) is assigned an internal IP address by DHCP, and it seems it has to be this way.
However, after installing Mikrotik RouterOS v6.45.3 on a machine with the above config, it seems to think that the ether1 interface (with the public IP address) is my LAN interface, at least it's on that interface that WebFig is available, even after enabling the ether2 interface (using dhcp-client) and rebooting.
The routes table, firewall table etc. are all empty.
What I'd like is for ether2 to be the LAN-interface (I know several answers states that there is no concept of WAN and LAN interfaces in RouterOS) and ether1 to be WAN (i.e. webfig NOT accessible on it). So webfig should be accessible on ether2.