SSD not detected in disk utility

Is the SSD an original Apple SSD or a third party SSD?

If it is an original Apple OEM SSD, then your SSD has most likely failed.

If it is a third party NVMe SSD, then you will need to boot using a macOS 10.13+ installer in order to see the third party NVMe SSD since older versions of macOS don't have the necessary NVMe driver required for a third party NVMe SSD. Your picture shows you using an older version of macOS as evidenced by the old version of Disk Utility in the picture. Try booting into Internet Recovery Mode using Command + Option + R to see if you can boot to the online macOS 11.x Big Sur installer. Unfortunately sometimes a Mac will only boot to the installer for the OS which originally shipped with the Mac from the factory. If this is the case, then you will need access to another Qualifying Mac compatible with macOS 10.13, 10.15, or 11.x in order to create a bootable macOS USB installer using the instructions in this Apple article:

How to create a bootable installer for macOS - Apple Support

Here is an article which shows which versions of macOS are compatible with various Apple hardware so you can identify a Qualifying Mac to use for creating a bootable macOS USB installer. Note: the Qualifying Mac does not need to currently be using the OS you want to download.

https://eshop.macsales.com/guides/Mac_OS_X_Compatibility

If you have a third party NVMe SSD installed and macOS 10.13+ doesn't see the SSD, then either the SSD has failed or perhaps the SSD Adapter is bad if you are using an M.2 SSD.

There is also a slim possibility the Logic Board could be bad, but I find 99% of the time the SSD is the weakest link here unless there is liquid damage involved.