How to Add the PowerApps to the SharePoint page
To add our Power App on a page within SharePoint, we will need to use a modern page. The modern pages are completely mobile responsive and are designed to function within the SharePoint mobile app.
Step 1- Add a new page to SharePoint.
Step 2- Select a blank page
Step 3- The blank page will look like as below, click on the EDIT button on the page
Step 4- Add a new web part in the column and select Power Apps.
Step 5- Fill out the Power App ID
Step 6- Click on Republish button.
All done, the Added App over SharePoint page will look as below