The y tho kid picture comes from a failed restoration of a painting of PopeLeon X, painted by Fernando Botero. I don't have any more information to share rn :D
But y tho is simple questioning something. It can also be the meme below, a variation of said meme, or a reference to the meme below. It's just a bastardization of "But why, though?"
John sees the above definition and is too dumb to figure it out himself that all he can say is "but y tho?"