Diskpart clean all.

running windows 10 21h2 19044.1766
I purchased a HP laptop AMD Ryzen 3 3250U 8 gig ram processor. 256 gig SSD storage.
all went fine until I tried to boot the rescue usb. since this laptop has no cd/dvd everything has to be on USB.
spent over two hrs with HP support. no idea what is going on. tried to turn it over to support that I would have to payl
I can return it monday but How can I do diskpart clean all to be sure all data is gone?
Is there a way to run diskpart without being in the install mode?
Any help would really be appreciated.
Shipinomore

it recognizes the usb in F9 but just sits there after select it. We tried to load a windows 10 install USB and the rescue USB from Macrium and nothing would work. HP also had me disable secure boot. nothing he had me do works.
I just created a dvd of windows 10 from an iso on dual layer and I have a external dvd burner and will see if that will load.
Shipinomore

right now when trying to create rescue usb I get a note saying gpt format is not supported it also shows drive E is fat32.

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Thank you for the suggestions. I seem to not sometimes have the correct format and need to prepare better.
shipinomore