No disk showing to reinstall macOS

Hi KimsMacBookAir,

Have you (re-)formatted your mac?

• Close/quit the installer
• Open Disk Utility
• Go to View>Show All Devices
• Click your Internal SSD/HD(APPLE SSD or SAMSUNG SSD) or “Macintosh HD”
• Click Erase
• In Format, Click on it, and select Mac OS Extended (Journaled)
• Click Erase to confirm
• Close/quit Disk Utility and open the installer to try again

So when you reinstall macOS and you can’t see the disk, first, you must erase a Mac

Hi Kim's MacBookAir,

Welcome to the Apple Community where some of us do our best to help each other.

Apple Support has a web-page online to help you step by step with re-installing Mac OS:

https://support.apple.com/en-au/HT204904

Hope this will help you be successful in reaching your goal :)

(Else feel free to "Post" here again)

I have this problem too last year

Incidentally Big Sur will want APFS format instead of HFS. You can format it HFS but the installer will likely reformat it to APFS anyway.

If the Disk format is incorrect, the installer shows the Hd that is Grayed out

Also, Apple recommends APFS or Mac OS Extended (Journaled)