Samsung Galaxy Note 8 (US-version) — What is using the storage space on my phone

I have a Note 8 that has 64GB of storage on the phone and 128 GB on an SD card. Of the main storage, I'm using 58GB of the available 64 and on the SD card, I'm using 15 GB of the 128GB.
I've moved my pictures and audiobooks to the SD card. What else could I move to the SD card to free up space on the Main storage?

On the phone, I use "File Manager +" to view and manage files. When I view the contents of the main storage I don't see anything that seems to be big. What should I be looking for? How do I do it?

I currently have the phone connected to my PC via USB cable. Using the file manager on my PC I can see the contents of the phone storage and SD storage. On the PC I'm also running TreeSize and it reports that the SD card is a total of 119GB and 13.9 GB is used. The main storage is 53GB and 47GB is used. I realize that the numbers may be different than what the Android app shows but I was just using the Windows App to see what it would tell me. TreeSize "should" show me the size of each folder but here it seems to have an issue and possibly does not report things correctly or possibly I'm doing something wrong. It reports that on 4.1GB of main storage is used in the main display but if I right-click on "Phone" (this is the main storage) and then select properties it shows that 47GB is used. Highly likely we have a user error here.

— modified on Sep 16, 2021, 10:50:22 PM