ABS/Limp Mode Help

Today when I got to work, my car went into limp mode and I got the Christmas tree lights dash board. The car says to check brakes and has the picture with all 4 wheels lit up red. I scanned the car with my accessport and it had a U0121 code for ABS. I plugged in my OBD11 and scanned the car just to double tap and it wasn’t able to connect with the brakes module at all. Just kept giving me an error. Not long after that, my battery full died (no power at all) and I had to jump it to drive again. The Cobb accessport had said my battery voltage was ~13.5-14.5 after the jump. I haven’t driven the car far at all, just around the parking lot to make sure it still worked but it’s still in limp mode. My question is, where do I start looking for a solution? I still get the ABS code after clearing. I’m still in limp mode. I have power steering and everything else seems to work ok. Any advice? Should I take it to a dealer/mechanic? If you have any other questions feel free to ask and I’ll answer as well as I can.

2017 Mk7 GTI S ~58,000 miles Never had any issues with ABS, battery, or alternator prior to this.