fwupdmgr get-devices --show-all
If you see your bios/uefi firmware, piece of cake.
fwupdmgr update [device]
However, fwupd generally runs at boot and as a daemon and will check automatically so you don't have to do this.
But, if you don't have it running for whatever reason, use those commands.
If that doesn't work, you might have to use a usb formatted to fat32 and have freedos installed on it along with your bios.exe file and boot to the usb to flash your bios.