Sweating a lot from upper back and face and forehead from exercise and from nervousness when other people sweat only a bit during exercise

See PCP first. You're not "other people" so don't worry too much. Sounds like you are a bit shy and nervous and sweating is symptom of social anxiety. Gradual exposure to people over time will hopefully help you but if the anxiety is too troublesome, you may need to consult a psychiatrist and also a psychotherapist. See pcp for appropriate referral.