To add and get acquainted with setting up the DNS to all MikroTik Router: select IP > DNS. A window will be opened as shown below:
1
Servers: you can add DNS servers IP
Dynamic servers: if you use a dynamic server for DNS, enter IP in this field.
Allow remote requests: with enabling this check box, the MikroTik will work as a DNS server.
Note that DNS setting in MikroTik is a cache DNS and resolves all DNS request to external servers.