php - using functions from ninja-forms says that the function doesnt exist

Question

When I try to use this function from ninja forms i get an error that the function doesn't exist.

$d = ninja_forms_get_fields_by_form_id('1');

What is the proper way to call this function or other functions from their documentation? is there an action that must be used?

the error that i get is:

Fatal error: Call to undefined function ninja_forms_get_fields_by_form_id() in

Answer 1

if anyone has this issue I resolved it by including this into the php file

require_once($_SERVER['DOCUMENT_ROOT'] . '/wp-load.php');

and that loads all of wordpresses functions into the php file so that i can use anything and it'll work.