I can guess what's happening, but not how to fix it, short of physically disconnecting the keyboard.
The startup commands are…
Cmd ⌘ R
reinstall the latest macOS that was installed on your Mac, without upgrading to a later version
This first one is in fact loading from your existing recovery partition.
These next two go online for Internet Recovery
The obvious cause is the filesystem or physical media can not make changes so make it reliable. Also, there are many different filesystem types and drives, so be sure your tool supports your OS and Hardware if you don’t try them for free first.
Do you have a backup? If not, do that immediately. You may need recovery software for this if the mechanism is ...
The disk "user" is the equivalent of having only a single password for
decrypting the disk.
You can add additional users for the boot volume using the fdesetup add command. (see fdesetup help for details)
You can add or change the recovery key after the fact using fdesetup changerecovery
You can remove users later using fdesetup ...
I don’t know a good way to test disks for sizing without a third party program or command line tools.
The former, I use SD Clone: https://twocanoes.com/knowledge-base/sd-clone-3-getting-started/
The latter - try these commands once you get the unix disk number from Disk Utility or another means - be 100% sure you have a backup of every single drive connected....
If you can you might trying erasing the disk and then reformat it. You will, of course, lose everything written to disk. If you want to keep what's on the disk you could copy it you main drive. Disk utility allows you to erase the disk and then reformat it.
After opening Disk Utility go to the Edit menu and at the top of the panal you'll see option to erase, ...
You could not have erased all the disks from recovery, otherwise there would be no Window Recovery to boot to. If you used the Disk Utility to erase all disks visible in the Disk Utility, then the result could be the same as the problem you describe in your question.
In other words, you did not know the Disk Utility does not show all the disks.
The EFI ...
The output given in the OP's question can be use to reconstruct the GPT. Once reconstructed, the output from the gpt -r show /dev/disk0 command should appear as shown below.
start size index contents
0 1 PMBR
1 1 Pri GPT header
2 32 Pri GPT table
For this specific error, do the following-
run Disk Utility/ First Aid a few times. There are cases where it may fix a bit of your partition map but still be unable to mount the partition containing your data, until run a few more times, this does look like a software rather than hardware issue
If you're running a very new Operating System and the drive was ...
Try erasing the entire drive, not just the volumes.
In Disk Utility, Hit Cmd ⌘ 2 (or see the View menu) to show Devices instead of just Volumes. Select the overall drive you will now see over the volumes (now in a disclosure triangle instead of separate) and Erase that, GUID/APFS.
If you aren’t following an internet recovery factory erase, here is the ...
This is because Apple pulled the Big Sur images and is only serving Catalina recovery from its content delivery network (CDN) or because you fall back to an earlier recovery that’s local to your setup.
Technical details are here: https://mrmacintosh.com/macos-big-sur-internet-recovery-unavailable-replaced-with-catalina/
Your windows keyboard is just fine ...
I have some possible solutions. The second option is probably simplest (if nothing goes wrong), but if it doesn't work, having an installer drive (first option) will give you a lot more options. So I recommend at least starting the first option.
Option 1: Create an installer drive
See Apple Support Document HT201372: "How to create a bootable installer ...
‘Other Volumes in Container’ are other volumes independent from your currently booted operating system and its data volume.
In your case diskutil list shows disk1s5 and disk1s7 as additional Data volumes. Check the contents of these volumes in Finder (or with OmniDiskSweeper pointed at these volumes instead).
The Base System (& the potential 20 or so tiny volumes you may be able to see below that) are part of your current Recovery session. You cannot erase them - nor do you need to. They are ephemeral & will disappear once you again boot to a normal OS.
You install your new OS to the main drive, once it has been erased.
Apple says you need to remove the disk from being a Time Machine destination for your Mac first.
If you want to change from unencrypted to encrypted backups, you must remove your backup disk and then set it up again.
Removing the disk doesn’t delete the contents of the disk though, so you should be ...
There is no way to limit individual APFS volumes that are used with Time Machine as per macOS 11.1. Any quota pre-set to an APFS volume would be removed by Time Machine when it takes over it.
The only way would be to partition the drive and create distinct APFS containers to limit Time Machine's use of the drive.