Reinstall apps that came with your Mac
If you delete an app, you can reinstall it.
To reinstall an app that came with macOS, reinstall macOS.
Reinstalling macOS doesn’t erase your information.
To reinstall iTunes, download it from Apple Downloads.
To reinstall an app that doesn’t come with macOS, use the Mac App Store.
If the apps came on a disc, and don’t appear in the App Store, use the disc to reinstall them.