for every one who has the issue:
TCP/IP Related Questions
I have two NIC cards in the MikroTik router and they are working properly. I can ping both networks from the router but can't ping from one network through the router to the other network and to the Internet. I have no firewall setup.
This is a typical problem, where you do not have routing set up at your main Internet gateway. Since you have introduced a new network, you need to 'tell' about it your main gateway (your ISP). A route should be added for your new network. Alternatively, you can 'hide' your new network by means of masquerading to get access to the Internet. Please take time to study the Basic Setup Guide, where the problem is described and the solution is given.
There is an example how to masquerade your private LAN:
[admin@MikroTik] ip firewall nat> add chain=srcnat action=masquerade out-interface=Public
[admin@MikroTik] ip firewall nat> print
Flags: X - disabled, I - invalid, D - dynamic
0 chain=srcnat out-interface=Public action=masquerade
This is linux so needs to be told what to do