boot raspberry pi 4b with flash drive

i downloaded homebridge img and im currently writing it onto a usb stick with the imager will i be able to boot my raspberry 4b using the usb?

It may or may not work. If it does not work, you need an SD card to customize it so that it works via USB.

Yes, all Raspberry Pi 4 has USB as a boot active by default. The early versions of Raspberry Pi 3 needed a bit changed in the OTP ROM (One Time Programable ROM) but that was changed and from Raspberry Pi 3B+ the Pis can boot from USB without doing anything. You can change the boot order in the EEPROM so USB is placed first as SD is first in the boot order by default.

But that should be fine

No need to do so