Adding microphones in all house rooms for google assistant

greetings HA’s geeks
first i want to say that am a total noob and i need enlightenment

lately I was researching on how to add microphones for google assistant so that i can cover all the house
i saw that the respeaker module( microphone module for raspberry) was a good choice

do i need the google assistant product so i could use the respeakers? or i can connect to the google server through the rspberry pi ?
can anyone direct me to a link or teach me on how to connect it ?

for example i need four or five of those microphones modules
i am guessing that the wiring process needs an some kind of amplifier so that it will avoid the voltage drop (the respeaker is mounted on the ceiling or on the wall and the raspberry pi is in another room on the server rack )

i really cant find a full guide for this topic ?
is it applicable to use 5 respeakers or normal usb microphones on one google assistant module ?

please help me
thanks

i found this link https://www.youtube.com/watch?v=g1qwX4QYoX8

can i connect this DIY product that this utuber made with home assistant ?

I can’t directly answer your question because my home is all Alexa. Alexa knockoffs by Eufy (from Amazon) are only $25 (pre-tariffs), so I have one in every room plus the basement and garage.