What Image processing models available to findout quantity left in a container?

Hello everyone,
I aim to assess the quantity of a substance, like salt in a container, and its emptiness, by employing image processing techniques. I’m curious if there are AI-powered API services available that can yield such results. Alternatively, I’m seeking advice on the specific image processing techniques necessary to recognize quantity patterns in images. I welcome any input or shared knowledge on this matter.

Until now, my exposure has been limited to services focused on image manipulation or Optical Character Recognition (OCR). If I aspire to create a custom solution, what steps should I take?

Providing some context about my skills, I am proficient in Python and have a basic understanding of JavaScript, including both Node.js and vanilla JavaScript. I am eager to explore and learn machine learning techniques or delve into fine-tuning existing models if that proves to be a crucial aspect of the process. How can I embark on this journey effectively?