Can a man get hereditary alopecia at a young age even if the other men in the family did not lose hair until late in life?

Yes: Everyone's genetically different (well, just about) since your environment will also affect how your genes present themselves. My point is that it's quite possible for someone to lose their hair earlier than everyone else in the family. If it's typical male pattern baldness, we can offer Finasteride & Minoxidil to try to slow down loss. But beware of side effects like gynecomastia, etc.