Chrome OS bios

--https://share.google/aimode/yNL9Kkbcg5gXjLeSq

Chromebooks do not have a traditional BIOS key or setup screen like Windows PCs or Macs. [1]

How Chromebook Firmware Works

Coreboot: Chromebooks use a specialized firmware variant called Coreboot instead of a standard BIOS.
Read-Only: The core system firmware is locked and read-only for security. It updates automatically through standard ChromeOS system updates.
No Boot Menu Keys: Tapping keys like F2, F10, or Del at startup will not open a BIOS menu. [1, 2]

Alternative Options

Check BIOS Info: You can view your current firmware details inside ChromeOS by opening the browser and typing chrome://system#bios_info in the address bar.
Recovery Mode: To access low-level boot or recovery functions, turn off the device and press Esc + Refresh + Power simultaneously.
Developer Mode: Advanced users wanting to install alternative operating systems must use specialized scripts (such as those from MrChromebox.tech) from within Developer Mode. [1, 2, 3]

To help you further, let me know:

Why are you trying to access the BIOS?
Are you trying to boot from a USB drive or install another operating system?

If you tell me your goal or the exact model of your Chromebook, I can provide the precise steps you need.