Some question about the bootable USB

[StayZe]

I want to create a bootable USB from an image file (ISO or other). Could you clarify:

1. Which image formats are supported (ISO, DMG, etc.) ?
2. Which tools you recommend to write the image (Balena Etcher, Rufus, others) ?
3. Which filesystem should the USB use (FAT32, exFAT, NTFS, APFS, HFS+), depending on the target ?
4. Are there specific steps to ensure it’s truly bootable (partitioning, MBR vs GPT, special options)?
5. About macOS ISOs found here: https://archive.org/details/macos-collection, are they compatible and legitimate for creating a bootable installer? Any precautions to take?
   Thanks in advance!