It depends on what OS you are using. If you use Windows you should launch the Search Bar and find Appdata” or “Userprofiles”. Then you can press the “Return” button and double click the folders “Apple computer” - MobileSync - Backup or use the link you can see above. If you use iOs you should Launch a Finder Window and choose “Go - Go to Folder” and type /Library/ApplicationSupport/MobileSync/Backup/. The full guide with screens you can see here rocketfiles.com.