Thank you so much to everyone for your help and ideas. I have decided that I will use a shallow bin (that i just purchased) and i will burry it in the ground so that she can get in and out easily and fill it with water. i bought some turtle food and ill put some food in the bin. ill check and see if she lays any eggs. If nothing happens, i will take her to a pond. As of right now im going to let her stay, since i dont want to be the reason for any baby turtles dying.