I tried reproducing it in my own way.

Place the camera directly below the abdomen, an ultra-low angle looking up at the person from directly below. Use a smartphone wide-angle lens from an extremely close distance, with the front abdomen taking up a large part of the entire screen, and the upper body and face placed smaller in the upper part of the screen. Strongly exaggerate the perspective, with the composition extending depth from the center of the body toward the face. A natural snapshot style with the camera tilted slightly diagonally and the horizon also slightly tilted. The person's gaze looking down at the camera.