I had my iPhone jailbroken and used MobileTerminal all the time. But I just wanted to go back to normal, and I have an app now that allows me to SSH to other computers.
Is there a way to SSH to my phone? I have its IP.
SSH server won't start without jailbreaking it.
You could probably use an app you developed or that you can run using a developer license, which will start the SSH on a port you want (pretending to test it).
TL;DR You can't.
In order to be able to connect to the (or any, for that matter) phone via SSH, it needs to run an SSH server that listens for connections. Although the iPhone theoretically can, Apple does not ship an SSH server by default (or at least doesn't enable it, not too sure).
This is why you need to jailbreak the phone and install your own SSH server.
Also see this Stack Overflow question: