How do I know which files to delete when I use the find duplicate files option?
Only you can decide which of your files you want to keep.
If they are not your files but system files then leave them alone, removing system files could break your machine.
I understand only I can decide which to keep. If I have 12 copies of one file, how do I decide which one to keep, because although I'm not sure, but I don't think I need them all? Thanks in advance for any suggestions
how to decide?
by looking at each one and deciding - that may sound obvious but would you rather be in control or have the programmers code decide for you?
If you look at the files in the list you attached you will see that each duplicate was created at exactly the same time but in different folders.
This often tells you that these are files that have been installed by programmes, and they need the same file in different locations to work properly.
I may be that there is only one actual file, with the others just being shortcuts that point to it.
If you remove one or more of these duplicates then the programme may/will not work properly, and you will then need to reinstall it to put the duplicates back and get it working again.
I would leave all the drivers, and anything in 'C:\Programme Files' well alone. You could break your machine altogether by removing those.
(Try another scan but make sure that you have 'Ignore','System Files' ticked in CCleaners Duplicate Finder. (It may still find some of those anyway)).
The rest of them seem to be iTunes files, one copy in '....\Music\iTunes\iTunes Media\...' and another in '....\Music\iTunes\iTunes Music\...'
I'm not familiar with iTunes, but again I suspect that there is only one actual file, with the other just being a shortcut that points to it.
Although it is possible that they may in fact be full copies. - See "Consolidate your iTunes Library" in the second link below.
These may help you with deciding about the iTunes files:
https://appsliced.co/ask/where-are-my-itunes-songs-stored-on-my-hard-drive
https://support.apple.com/en-us/HT201625
You may want to ask more about the iTunes files on an iTunes forum. Here's the official Apple one, there are others:
https://discussions.apple.com/community/itunes/itunes_for_windows