Upgrade error - OJS to OJS

After upgrading from OJS to OJS received only the structure of OJS, do not load setup page, just

It is the same with previous versions. PHP is used from 5.6 to 7.4.
Where is the exact problem?

Hi @Lazar_Stosic

It seems that your server is set to show the OJS folder as a list of items and not to render the PHP files.
Have you check your server logs to review any message?

What is your current stack (webserver, PHP, DB versions) ?