In general, it is
/opt/cpanel/ea-php##/root/usr/bin/php
php 7.2:
/opt/cpanel/ea-php72/root/usr/bin/php
To find what version of php you are using:
php -v
/opt/cpanel/ea-php72/root/usr/bin/php -v
Find ini settings:
/opt/cpanel/ea-php72/root/usr/bin/php -i | grep memory_limit