I don’t want to discourage you, but I do feel like I really need to warn you because the performance hit is unreal on Skyrim SE. I would 100% recommend you stay away from an ENB if you don’t have a top of the line GPU and you’re playing Skyrim SE. While there are some optimization tweaks, if you’re playing Skyrim SE ( Special Edition) they are a nightmare unless your GPU is NASA level.
There can be lots of unexpected bugs and issues, as well as general brightness problems ( your game might become too dark etc). Generally speaking, they are compatible with many other mods that edit the game’s visuals, but you really need to pay attention to this because not all of them will work with all other mods you might want to use. They come in many different presets or versions, depending on your preferences and how you wish your game to look & feel. ENBs are post processing effects designed to greatly improve the visual aspect of your game.