I click on Apps it takes me to a page that shows a tab for "My Apps" with the paragraph saying "Apps can help you be more efficient" but there is now way to add an app.

It's nice to have you here, mahesa.

Let me share some insights about the Apps menu in QuickBooks Online. It has been added to the left menu. However, this feature is not yet working for QuickBooks international version. It only works for the US version of QuickBooks. 

For now, we're unable to give you a specific turnaround time as to when this be available for you. Rest assured that we're working for the App integration for international versions.

I would suggest checking this article for some video tutorials about the uses of different features in QuickBooks Online: Tutorials for QuickBooks Online

Please don't hesitate to add a Reply if you have any other concerns.

@mahesa 

What kind of 3rd party app do you need? We may recommend you something to explore.