To setup crontab in SugarCRM to enable Scheduler.

In Sugar copy the command that is displayed for Cron.

In cPanel click the Cron icon
Click add cron job and enter the command that was copied from SugarCRM.

Next open File Manger in cPanel.
Browse to the root of your Sugar install.
Select config.php
Click Copy to create a backup of the original file.
Select config.php and click Code Editor.
Find:
'localhost'
Replace with:
'127.0.0.1'

Click save.

Test in Sugar to see if scheduled tasks are running.

If there are any issues please contact support.