Beginner level ability to identify scarab beetles

Scarabaeid beetles have beautiful shiny bodies, and some of them have cute antennae that look like fans. Whenever I see them on a flower, I always take a photo. After that, I go back home and research the name of the scarabaeid beetle in my insects picture book, but in most cases I could not identify the species due to their very similar appearances. It's also difficult for me to identify the type of ground beetles and dragonflies, but scarabaeid beetles are the most difficult. I want to graduate from beginner level first.