https://www.dell.com/support/kbdoc/sk-sk/000128928/flashing-the-bios-from-the-f12-one-time-boot-menu
Flashing the BIOS from the F12 One-Time Boot Menu | Dell Slovensko
Learn how to update the BIOS on your computer using the BIOS executable file that is copied to a USB drive from the One Time Boot menu.
flashing the biosone timeboot menuf12