Set a realistic budget, say <$500 "all in" (bike, helmet, lock, etc)
Find three local shops that carry legit bike brands (Trek, Specialized, Raleigh, etc)
Visit all three, explaining what you're looking for. Be honest with yourself and the sales person.
Buy the bike you like the best from the shop you like the best.
Ride the wheels off of it with your family and friends.
-Kedosto