Can I create a form with a menu and multiple forms, such as in the demo app Northwind Traders that comes with MS Access. I would like to be able to create apps that are more than just one form, with view, edit and create.
Feel free to point me to a demo where it is shown how to do this.
Could you please provide a screen shot of the form you are referring to in MS Access?.....I think I know which one you're referring to, but I'm not 100% sure.
In any event, Yes, you can create a menu with multiple forms. I believe you'll need to combine galleries and forms to get something close to that sample form. You can see an example of multiple forms when you generate a PowerApp from a SharePoint list for example. Even though you might not want to connect to a SharePoint list, that is a great example of browse, item display, and edit/create forms which can be done with most connections available. Also, check out the "Budget Tracker" app in tablet mode. Notice how the gallery on the left is similar to a 'parent item' where multiple 'expenses' are like the child items. So on that one screen in the budget tracker you have something close to customers to orders.
The example screens related to SharePoint list apps (remember that the data source doesn't have to be SharePoint if you want to take a similar approach):