So I'm trying to see if I can get another debit card. I'm over 18 and already have one but my dad checks it from time to time. I want another one that he doesn't know about and I can put some money on. Would I be able to get another one?

You would open another account and be issued a debit card for that account.

If you are over the age of 18, you can legally open your own bank account, you no longer need your parents' signature. So, open your own account and get a debit card tied to that account.

Probably some prepaid card not tied to a conventional bank, though you may have to be 18.

Get a prepaid card.

http://www.hrblock.com/financial-services/emerald-card-services/index.html

You would have to open another account on your own.

sure just have two different bank accounts