make Raspberry Pi 4 GPIO pins low while Startup and shutdown

Question

I have used all 27 GPIO pins of raspberry pi for my hardware out of which few pins are active high at the startup as per Raspberry pi GPIO documentation.

I want to make GPIO0, GPIO6, GPIO7 and GPIO8 low while raspberry starts and shutdowns

I have tried to make GPIO low by adding some commands in config.txt.

gpio=0=op,dl
gpio=6=op,dl
gpio=7=op,dl
gpio=8=op,dl

but not working as expected