Computer boot up. How to run your code?

Question

assembler

The result is needed:
1) Starting the PC
2) Instead of the OS, run your code from a disk or flash drive
3) Get as much information about the hardware as possible.
Please direct me to the correct information. Thank you.

Answer 1

Bootable CD/USB Google.

Answer 2

How to run a program without an operating system - the first page of Google. Shame on you, comrade.