Q: Passcode

Connect the iPod to your computer and restore via iTunes.  Of necessary, place the iPod in recovery mode and then restore. For recovery mode:

iPhone and iPod touch: Unable to update or restore

How do I get my passcode if I have one?

You would have to remember it, since you would have been the one to add it. If you cannot remember it, use this link for instructions. If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support

How do I get my Ipod in recovery mode or restore?

Use the link I provided.

yes, i forget my passcode

Read back in this thread and use the link provided regarding the forgotten passcode.