How to write boot sector code? (x86 pc)

Question

I am going to create a tiny operating system but I don't know how to write boot sector code. It needs to load a program called loader.bin into memory and execute it.

Answer 1

I wrote my first bootloader thanks to this guy:
https://youtu.be/YvZhgRO7hL4
Maybe it'll help you too.

The sound does go out of sync in the later videos in the series, but just deal with it.