I started some processes with nohup and they aren't working correctly so I need to find and kill them but I dont know the pid or anything.
SSH in and then use the ps command to list running processes in conjunction with the grep command to filter that result list down to what you need:
ps aux | grep something
"ps aux" returns a list of all processes currently running "grep something" takes that list (via the pipe ("|")) and just outputs strings that match "something".
So for example if you wanted to find the httpd process you could use
ps aux | grep httpd
The results will contain the PID you can use to kill them.