So there are a bunch of words I don't know in your responses. Thanks, by the way, for answering. So I could:
buy a digital amp and use usb
mic my old school amp
buy a 1/4" to usb cord and plug the guitar straight into the computer

no matter how I get the guitar into the computer, am I running it through a music program like garageband, audacity, etc? or is jammr set up with a mixer, effects, etc.?

I have a Focusrite Scarlet2i2 that makes my microphone work. I don't know what it does but is that something useful for this?

Why do you talk about recording? Aren't I jamming? as in playing live? why would I want a file of what I played before?