My serum testosterone level is 673 ng/dl. i have very less facial n body hair n poor muscle development. what should i do?

Exercise: Facial hair is based on genetics. What kind of facial hair did your father, grandfather, uncles, etc. Have? Your testosterone is normal, and not a problem. Muscle development can be radically improved by diet, exercise, & weight loss ( if needed). Avoid supplements which won't help and can harm you. Don't get your medical information from friends, tv or the internet.