My Book is almost full with no idea why

I am not an expert on the MyBook apparently. I recently purchased this item to put all of my families photos and videos on an external hard drive. I have used up about 3GB out of 4GB of the hard drive. I am 100% sure I don’t have that many photos and videos. I also have a image duplicating software to rid of all the image duplications. I do believe I may have other files that are duplicated. How can I go into my drive to delete the unneeded files? Do I need to use the WD Utilities? Not sure what to do at this point. Any help would be greatly appreciated? I believe that the drive has backed up my files numerous times. I know I need to check the backup schedule, but just need to see what is in the entire hard drive. I cant see all files.

Thank you for any help.

You can access your hard drive to delete unwanted content in the Computer section of your system. Your WD My Book should be listed alongside your C or D drives.

However, depending on how you added content to your unit then deleting files may corrupt your backup and you may have to start over. What is the name of the application you used to handle your automatic backups?