How to update Xcode?
You probably just install the current version from the MAS.

https://itunes.apple.com/app/xcode/id497799835?l=en&amp;mt=12

The command line utilities are included within the Xcode bundle. On first launch symlinks to the utilities are installed into the system so they can be accessed from the Terminal/command line.

There is also a separate Command Line Tools package available from the Developer Account download archive (needs an Apple Developer Account).

https://developer.apple.com/download/more/?=for%20Xcode