Several ip-addresses via ethernet on one Mikrotik interface

Question

Mikrotik

The provider gives a pool of ip-addresses via ethernet. The router is Mikrotik.
For example, let's take the following scheme: an Internet cable from the provider is connected to the first port (and there are two external IP addresses), the first LAN to the second port, the second LAN to the third port.
It is necessary that the first locale go to the Internet from one address, the second from another, and all through the first port. Is this possible on Mikrotik and how? Or which way to read?
It was possible to make such a scheme: a cord from the provider to the switch, two cords from the switch to the first and second ports of Mikrotik, on each port we configure our interface, to the third and fourth ports of the LAN, and accordingly configure the routing.