Hello there,
Type cmd to run in the command prompt instead of PowerShell and then re-enter bcdedit command.
You can also use bcdedit /? and get a listing of the commands. Since you are not using an {ID} for the commands you are addressing them to the {current} OS Loader.The values being mentioned may not already be in the BCD store but you can check that from the bcdedit listing.
Similar discussion here https://answers.microsoft.com/en-us/windows/forum/all/bcdedit-is-not-working/742dd414-d89c-49e3-a3e8-9eafc386f731
Hope this resolves your Query !!
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