My dad told me to be careful with my knife because it could be a considered a concealed weapon?

Your father is right in his intentions, it is also based on how the laws of your state is written for knife possession and most importantly, where you carry it.

just keep it in your pants pocket. most people use the belt clip thing to clip it into their pocket, with the majority facing in the pocket. It isn't illegal to carry a knife, unless it doesn't abide by state laws. for instance. where i live i cant have a knife with double sided sharp edges, a butterfly knife, any ballistic knife, knife longer than your palm, etc. i will put a link in my source which has knife laws for all 50 states. Please also note that you can never bring a knife into an airport, post office, police station, school, or any other federal, or state official building. and you have to be 18 to have, or purchase one.

It depends on the state your in and age. You should do some research, I know hear in va, you cant have a concealed weapon at all unless licensed for it, i would check before you get into any legal trouble

in your pocket closed so you dont cut anything you dont want cut

Your father is correct.