To make an AI photo realistic is to convert a generated or drawn picture into one that looks taken with a camera, while the scene stays recognisable. Unlike a light fix, it changes the rendering of everything: skin, fabric, stone and glass get real texture, and the light follows one clear source.
On AIImageEditor.pro the tool runs Nano Banana 2.1 at 2K with an instruction built around what makes a photo read as real: a main light with the shadows it would cast, materials you could touch, depth of field, slight vignetting and fine grain. The same subject, pose, composition and scene are kept.
Because it changes the style on purpose, use it for illustrations, anime, game screenshots and CGI. If your picture is already photographic and only looks too smooth, the AI Image Humanizer or Remove AI Look changes less.