Can you add several images (in addition to the 5 included) on one product?

Yes you can.
First you upload extra images (or files eg PDF) via the "File Manager" (not active in a test store due to security risk),
then you can upload the image / images via the product editing page.
You can also create extra pages with images via Page Manager and link to the page from another page (eg product page).

There are also many so-called "modules" that we can install in your store. For example. to view a slide show or movie.