Why is one of the two networks not available in Mikrotik?

Question

Computer networks

The local network 192.168.1.0 is connected to the second port of the Mikrotik. Address 192.168.1.254/24. DHCP, DNS on the domain controller.
The fifth is connected to 192.168.100.0. Address 192.168.100.1/24. DHCP is configured on Mikrotik. The master port is disabled.
The problem is that computers from the first network ping computers from the hundredth network, but not from the first network. Separately, routing was not configured anywhere. DHCP is simply configured and the Internet is forwarded for the hundredth network in Mikrotik.
How to make the first network available from the cell? Ideally, make access from only one address of the cell network to a specific address in the first one.

Answer 1

Well, I dare to assume that you have the 1st network in the 100th NAT'it. And in general configure normally routing.