My daughter had a mild one in college (not sports related) - which kept her away from school work for only a few days…
The biggest thing is no screen time - none - including cell phone. She used Siri or Alexa to send texts and communicate using her phone. Had others read her homework questions aloud.
I also second the PT. My daughter most likely had whiplash from her fall, which went undiagnosed. We realized it months later when she got aural headaches and ended up with TMD symptoms for almost a year. You need a good PT who does a complete workup to determine exactly what neck and other muscles are injured and how to get them back in working order.