Reinstall macOS on Ubuntu MBP
Instead of selecting the Reinstall option select the Disk Utility option at the bottom.

This will run Disk Utility and allow you to perform all of its usual functions, such as repairing your disk and formatting it.

Reading between the lines it's most likely you'll need to format the drive to make it available for the macOS installer. Once you've done this you can quit Disk Utility and you'll be returned to the previous menu to select the Reinstall option again.