Link Public IP address to Local in Mikrotik

Example of Destination NAT

If you want to link Public IP 10.5.8.200 address to Local one 192.168.0.109, you should use destination address translation feature of the MikroTik router. Also if you want allow Local server to talk with outside with given Public IP you should use source address translation, too
Add Public IP to Public interface:

/ip address add address=10.5.8.200/32 interface=Public   
   

Add rule allowing access to the internal server from external networks:

/ip firewall nat add chain=dstnat dst-address=10.5.8.200 action=dst-nat \
 to-addresses=192.168.0.109 
   

Add rule allowing the internal server to talk to the outer networks having its source address translated to 10.5.8.200:

/ip firewall nat add chain=srcnat src-address=192.168.0.109 action=src-nat \
 to-addresses=10.5.8.200