The PHP setting max_execution_time is the number of seconds PHP will allow a script to run before PHP terminates the script.
The best way to change the PHP max_execution_time setting for an app is to create a .user.ini file in the app's public directory.
This file should contain the following:
max_execution_time = 120
where 120 is changed to the value you need to set for your app.
For information on changing other PHP settings, check out our tutorial on using .user.ini files.