Why won't BIOS open on asus prime z370-p motherboard?

Question

ASUS

I assembled the computer, I start it, everything works, but the BIOS is not shown (Cable Not Found is shown on the monitor, the monitor is connected via HDMI).
Accessories:

• Motherboard: Asus prime z370-p
  
• Processor: i5-8400
  
• RAM: corsair Vengeance LPX 8gb DDR4
  
• Vidyuhi no
  

Answer 1

> everything works Is there a
single squeak when you turn it on? There seems to be an indicator of POST codes next to the RAM connector. What is displayed there?
> Processor: i5-8400
As a variant, the BIOS knows nothing about it.