Passing Parameters from SharePoint 365 to Powerapps

I’m just starting out using Powerapps and want to pass parameters from my SharePoint page to my powerapp.

Problem 1.

When I use the ‘Add a Powerapp’ option in SharePoint it works fine without any parameters but as soon as I try adding a parameter say, ?PageName=DDG onto the end of the URL the powerapp disappears from view.

Problem 2

I have also tried using the ‘Embed’ option with an HTML iFrame statement. This seems to allow parameters to be added as the PowerApp remains in view in SharePoint. However I don’t know how to access this parameter from the powerapp itself. Whenever I refer to the parameter (PARAM) it doesn’t recognise the name I have used as I have not initialized it anywhere in the powerapp, but if I initialised it it would lose the content passed over.

I’m new to this so any help would be greatly appreciated.

Regards

Pete