Hi lemonsteak123. The asset is public domain or basically CC0. While the textures used here are not created by me they are CC0 as well.
Basically, this is free to use even for commercial project with or without attribution to me, 'as is' or doing the modifications you need to suit your likes. You can put my alias/name in the credits of your game, but that is optional. A donation, while not mandatory, will be greatly appreciated.
Wish you luck in your game.
:-)