What Dan said - Visual Novels are IF adjacent. They tend to have a low ratio of choice to time spent reading, but often will branch widely and the choices tend to be dating/relationship style “which characters are you spending time with?” Often there is a running clock or calendar and they might have sim-elements and some stats - spending a morning in the library might improve your intelligence and perhaps will give you new conversation options with a smart character or open up branches you wouldn’t have before.
The basic gameplay is usually a background of the location and paper-dolls of the characters (which are often quite varied in expressions and sometimes animated) slide in and out from the sides as they talk, or have portraits next to their dialogue scrolls at the bottom of the screen. Occasional choices pop up over the screen in a list that the player selects, though some games will have more extensive interfaces, clickable maps, or occasionally even 2D or 3D navigation.
Doki Doki Literature Club is actually not a standard VN (major spoiler: it’s actually a stealth psychological horror game that plays on the meta of the Virtual Novel genre), but if you were to only watch the first 45-60 minutes of a play through of that game, it lovingly leans hard into the dating-sim VN tropes and is a good example of the style and feel these games usually have. There are probably better examples of basic VN, but I was really into this game for a while based on the meta-tricks it plays.
I actually reviewed a Visual Novel that was entered into Spring Thing 2018:
The most common VN authoring engine is Ren’py, although there is the commercial Visual Novel Maker (from the makers of RPGMaker) and I’ve also heard of Tyrano Builder.