PHP Extensions config files directory?

Where can I edit the config file for extension for example the PHP-Opcache and PHP-redis to edit certain value for example, opcache.memory_consumption = …




This was of great help to me too.

@usmannasir and @sehatalaislam
can you please guide me to the list of necessary/recommended PHP extensions I need to install/enable?
And also I would like to know the best config for the Redis & Opcache setting for hosting with 16GB