kill node

killall node

ps aux | grep node
kill -9 PROCESS_ID

sudo kill -9 $(sudo lsof -t -i:8000)

The Difference Between kill and pkill
The kill command is a wrapper to the kill system call, which knows only about process IDs. pkill can determine the process ID based on things like, process name, owner of the process or session id.

Syntax:
$ kill 1234
$ pkill -f node

lsof -t -i:3000

6279