Search for product prices Lazarus Delphi

I've never asked the site before, I do not know if I should start with greetings or get straight to the point. My goal is to set up a form that searches the prices of supermarket products, to find the cheapest, something close to what the buscapé does. I do not know how to do this, I did not find any API open that would break the branch. I am a layman, I work in a restaurant and I would like to reduce costs, I have some way with Lazarus, I have done some programs before but relatively simple.