I wanted to put money into the game, but I did not want to put it with a credit card, but with the steam card that is bought in stores, how do I put that card in the game, does anyone know?
You should only need to have the right amount of money in your steam wallet. So purchase a steam card and use it to add money to your wallet I suppose. If you launch the game with Steam then there should be an option to press charge when you enter the item mall in game. You press that and a web page pops up. It'll give you an option of what amount of rp to purchase. Select what you want and continue. It should take you to the steam website. If you don't already have enough funds in your wallet it should ask you if you want to add some. So make sure you added money with the steam card. If you have enough it should ask you to confirm the purchase of rp with your steam wallet. Hopefully this will work out.
alucard already helped but as a side note if when you click the charge button in game it fails to give you the option to pay with steam just send in a ticket on the website. it took around 3hrs and they got mine working for me