BLine_out_L goes to Return L
BLine_out_R goes to Return R
Line_out L goes to SpkoutL
Line_out R goes to SpkoutR
AGND goes to Ground

MICPWR goes to MICIN
MIC2 goes to MicBias

Ok, mic in is connected to +5VA, Mic bias is for condenser mic and if your mic is moving coil type this doesn’t need to be connected. Ground is connected to Agnd. Spkout L is for Bline out L or left channel headphone, Spkout R is for Bline out R or right channel headphone. Don’t worry about return L and R you don’t need to connect these either. You’ll need a ground possibly for headphones but it may be common ground (earth) for mic and phones. That should work. If all else fails and you abandon connecting these terminals then you can get a USB headphone and microphone that replaces these anyway from a reputable Computer shop. Good luck, hope that helps!