The volume recovery on disk1s3 couldn't be unmounted because it is in use by process 0 (kernel)

From the screenshots, it shows the local recovery partition disk1s3 is mounted which tells me you are booted into local recovery mode instead of Internet Recovery Mode. If you held Command + Option + R, then perhaps it didn't work correctly. I've seen it happen on some systems. You may want to connect the computer directly to the router using an Ethernet cable for a faster & more reliable connection and to bypass any possible WiFi issues.

If the computer will only boot to the local recovery partition, then you could create a bootable macOS USB installer using these instructions:

https://support.apple.com/en-us/HT201372

Are you sure you are booted into Internet Recovery Mode and not just local Recovery Mode? Local Recovery Mode is accessed by Command + R, while Internet Recovery Mode is accessed with either Command + Option + R or Command + Option + Shift + R. I'm not entirely certain whether you can erase the physical drive while booted in local recovery mode.

JTATX04 wrote:

Its says ScanDisk SDSSDA960G and I am getting an error saying it cannot unmount the disk.

You do want to choose the "SanDisk SDSSDA960G" to erase which would be your physical drive.

To see what is happening open the Terminal app and run the following two commands. Post the results here:

diskutil  list  internal

mount

In Disk Utility click on "View" and select "Show all devices" which will then show the physical drive in the left pane of Disk Utility. Erase the physical drive instead of the containers or volumes.

Yes. Usually it will say "Apple HDD...." or "Apple SSD...." if it is an original Apple drive, otherwise it may list the name or model of a third party drive.

No, sounds like the Disk/SSD you're booted from.