Different PC brands use different BIOS keys. Most modern motherboards use the DEL key, but laptops and desktops are less consistent.
When you first power-on a computer, it goes through a very quick POST (power on self test). If you can hit the correct hotkey before the POST is completed (or hold it down as you hit the power button), you will get into the BIOS menu. If you don't know the hotkey for your computer, you can look and see if a message comes up during POST, telling you what key to press.
BIOS Keys by Manufacturer
Here's a list of common BIOS keys by brand. Depending on the age of your model, the key may be different.
ASRock: F2 or DEL
ASUS: F2 for all PCs, F2 or DEL for Motherboards
Acer: F2 or DEL
Dell: F2 or F12
Gigabyte / Aorus: F2 or DEL
Lenovo (Consumer Laptops): F2 or Fn + F2
Lenovo (Desktops): F1
Lenovo (ThinkPads): Enter then F1.
MSI: DEL for motherboards and PCs
Microsoft Surface Tablets: Press and hold volume up button.
Origin PC: F2
Be careful when making changes to your settings there. You could end up disabling key components.