The page editor is loading endlessly when you click edit page in Step3.
The problem could happen when the max execution tome and memory limit are low. You can update these values in cPanel -> PHP Select Version -> PHP Selector | Options, and change:
max_execution_time = 360
memory_limit = 512M
Change to higher is the error still persists.
If you cannot see these features on your control panel, please contact your host provider to update it for you.