Would you like to get an element of a page, through its "coordinates"? [closed]

I would like your help, as I was asked to develop an extension for google chrome, which takes a certain value from a particular page, but I do not have much programming knowledge with javascript, could anyone help me? I saw something related to DOM, but I just found it to get this element by ID, CLASS or METHOD, but none of these elements is unique in the page that I want to get the information Thank you in advance