What you did there was change your computers IP address to the same IP address that another computer or your router. You do not need to change these values when you port forward.
yea and also i port forwaded its at 28000 where it should be and my friend says it said server is dead i dont understand
don't just forward 1 port, forward a range of ports 28000-28030 or whatever that was
If you expect help, tell us what router you have