I followed directions and I tried both line out 2i2 and stereo mix for recording and neither work.
What are you trying to record? Can you hear anything through the interface? (You don’t always record exactly what you hear, but if you can get analog sound into the device and out of your soundcard, that proves the hardware & drivers are working.)
Have you tried the Ableton Live software that came with your interface? (Although, Audacity should work with anything that has Windows drivers.)
I followed directions and I tried both line out 2i2 and stereo mix for recording and neither work.
You can’t record line-out. 
It’s an analog output, and it’s for playback or monitoring. You record from something plugged-into line-in or microphone-in (on the front of your interface).
You can record line-out from your interface if you connect it to line-in on your soundcard (if you have a soundcard with line-in).
Stereo Mix is not supported on all systems… It’s becomming rare. But if it shows-up as an option, it usually works. Stereo Mix should record whatever you are hearing from your computer speakers (or headphones) If you are not hearing anything, you won’t record anything.