You Doctor. Your primary doctor would be a great place to start.
PCP or rehab dr. First see your primary doctor to see if you need inpatient or outpatient rehab. If due to a specific cause like a broken bone, you could also see your orthopedic surgeon e.g. These doctors may then refer you to a rehabilitation doctor who specializes in evaluating patients for rehab and determining the proper setting, rehab plan, and duration. You may or may not need inpatient rehab admission.