I created a PowerApp and connected it to a SharePoint list, but i didnt create it from SharePoint. Is there a way to now use that powerapp as the defualt edit form? if not is there a way to hyperlink to the powerapp and pull up all the field from that form?
The way @SKimble119 suggested, is that you embed an app on SharePoint Pages following the steps here.
But if you just want your SharePoint list items to show/edit in the Form customized as from PowerApps, then I think you will have to do this in SharePoint list from the beginning.
This is because that your app was created as a standalone app and it is different from a customized list form. The list form app that you create from SharePoint is a special type of PowerApps app that can only be used within a SharePoint list. These list form apps don't appear in your app list in PowerApps Studio for web or PowerApps Mobile, and you can't run them outside of the SharePoint list.
About how to create a customized list form in SharePoint site, please refer to: