Doeo is a game in English, based on a Japanese game called Moai no Su (click on the top option on the start screen in order to play). Try them both and you’ll see that they’re extremely similar, basically the same game with different dressing. This isn’t a coincidence of course, the Doeo dev has an explanation here, but it basically boils down to the fact that Moai no Su was a Japanese game in Japanese and popular in Japan but pretty well unknown among English speakers. So he made an English version.
So what sort of game are they? Well there used to be a genre sometimes called “arena shooters” back when light guns were common. That’s the closest analogue I can think of. Basically a bunch of things pop up and you “shoot them” (touch them) with your mouse. That’s it. In this case it’s the presentation which makes it work.