Sounds like a cutie. Getting a frog depends on the size of home he has, it's recommended to keep them in an at least 1gallon sized home. Also, the type of frog you're probably thinking of is an african dwarf frog, those little guys who float alot.lol. The betta should be fine by himself, sometimes they rather prefer it so I wouldn't worry about him getting lonely. Best of luk and Congrats!