How to make AI model ?

I'd recommend seedance. It has become one of the standout AI video models recently. If you use a consistent reference image and a good prompt, it does a solid job of keeping the same face and overall appearance across scenes

Higgsfield would be good fit to make not so hardcore content, for its ease of use, given you may not be able to understand complex comfy ui flows

like someone else mentioned in here, take pics of model from various angles and have gemini generate a model 360 sheet which will become your reference point for all videos.

For that, you are going to have to look into Comfyui work flows. That is whats going to allow you to have a very consistent Model body across all the videos/images you make.