My friend is trying to buy LFS from a 50 dolalr gift card that has a visa/depit logo on it but it wont work. does it have to be a really debit card?

Try the localised sales points listed on the lfs website. Maybe you can pay them and get the s2 voucher and then activate it here

No, the card does not need to have any credit. If it's a valid Visa, then it should work.

Try using PayPal with that card (LFS accepts payments through PayPal as well).