It will show PHP the path to your custom php.ini File.
deny from all
If there is no .htaccess file you can create a new text file using the CPanel File Manager. Note that there is a dot at the beginning which makes it an invisible file.
If you don't see files that begin with a period (dot) then read How to Show Invisible Files in CPanel File Manager
The php.ini file is recursive unless overridden by another php.ini file.
Put PHP Option directives in the php.ini file.
Some common examples are:
post_max_size = 64M
max_input_time = -1
max_input_vars = 1000
PHP memory limit = 128MB
(-1 means unlimited)