The best I can figure is that it is a California treefrog, Pseudacris cadaverina. Check with your state laws to make sure this is legal to keep. Oh and it's not "breed", its species. Breed is a verb or action. Frogs sre not social animals per se, so he is fine by himself. I like to keep mine in pairs or small groups for breeding purposes. My guess is you can keep him like a Pacific chorus frog, Pseudacris regilla (see care article).