Q: how do i delete songs off my ipod nano?

Connect the iPod to your computer, and on the left-hand sidebar of your computer's iTunes (if you don't have the sidebar showing then control-S on a PC should get it to show) select 'Music' under the iPod device :

And use the right-hand side of the iTunes screen to select and delete the songs that you no longer want on it.

Or if syncing music to it automatically change your sync selections so that what you don't on it are no longer selected