M1 Mac, can not find "memcached.so"

Hello.

I want to use memcached cache server from my m1 laptop.

It is my .env file

CACHE_DRIVER=memcached
SESSION_DRIVER=memcached
MEMCACHED_HOST=memcache-server-ip

Firewall, memcached.conf settings on memcache-server-ip are all fine.

On my laptop, I installed

brew install memcached 
brew install memcache
brew install libmemcached 

in /opt/homebrew/etc/php/8.1/php.ini

I added,

extension=memcached.so

it is rebooted and php command was not working .

I searched extension file but it failed.

sudo find / -name "memcached.so"

I reallized there is no memcached.so file on my laptop.

How can I use memcache extension on my M1 laptop.

I can not find good guide on internet.