mac see what is running on port code example
Example 1: kill all server 5000 mac
#First run this, to get port information (with the port you want to kill)
sudo lsof -i :3000
#Then run this, with <PID> replaced by the value in the column returned by previous command.
kill -9 <PID>
Example 2: mac terminal find process by port
sudo lsof -i tcp:3000