Change memory_limit error

[Ckubs]

How to increase memory_limit and max_execution_time for a website? I don't see any option to do it for a particular domain and when I click Server > php fpm configuration, whatever I change there I get: "Error: php-fpm7.0 failed to start with new config".

I'm using a VPS with 1GB allocated RAM.

Thank you for any help.

[skurudo]

/etc/php/7.0/fpm/php.ini ?