Don't just leave, at least leave a note and tell your dad so he wont tell the police. I actually don't think you should do it, but i can't stop you, so just make sure you're ready to walk across the country.
Do you have route planned out?(cities to stop and rest at)
Do you KNOW you have enough money?(plan out your expenses and stuff)
Maybe your dad will give you some more money, cause you'll probably need it.
Tip: Keep your money in various places on you. Not all in your bag or in one pocket. Put some in your shoe, some in your bag, some in pockets.
Good luck i guess.