You have your work cut out for you. You can place all 80 illustrations in a new ID file, but both the index and TOC features require reading native text on a page, not the text inside your illustrations.
You can add a new layer to the document and set it to non-printing (very important), and on that layer add a text frame on each page you want to list. Type whatever you want to appear in the list in that frame. I would use a Table Of Contents, myself. You can have as many of them as you like, they can be anywhere in the file that you like, and they can be sorted alphabetically. They're also faster than indexes to create.
TOC is driven by Paragraph Styles, so you must assign a paragraph style to the content you want to list that will not be used elsewhere for things you don't want to include. If there is nothing but illustrations and your added tags in the file, you could use the default [Basic Paragraph] style, but I suggest you create and use a new style just for the TOC tags. This can be sthe same style you want to apply to the listings themselves inside the TOC, or something different.
The TOC will pick up the "logical" page numbers assigned by the Numbering and Section Options accessed through the Pages panel. You can crop the illustrations so your original numbers are hidden and add a Current Page Number marker special character in a text frame on the Master page, or you can leave your numbers and just make sure you set the section to start at page 1 where your page 1 illustration is placed, and so on. For a booklet it would be normal to leave the cover and inside cover un-numbered and start a new section with page 1 at the first page of real content (which should be a right-hand page). ID will complain about duplicate numbers so you must go back to the first page in the file and open the Numbering and Section Options agian to change the "style" of the numbers in that section.