Power App embedd in Power BI using Dynamics CRM Data

Power BI consumes a data source, (without advanced witchcraft) it cannot write back into the data source.

The PowerApps app can do both - it can connect to a recordset/gallery, it can display the data, and it can write back into the data source.

If you want both to cooperate then you need to cut down on the PowerApps functionality. Don't use PowerApps for displaying data, only use it for the data entry.

Once that part is done you can add the PowerApps visual to your Power BI Desktop file, and wire it in . That means you need to explain to the PowerApps visual which datapoints it should pull from the Power BI dataset.  Technically you can also not do that, and leave the PowerApp visual unwired. That means the user can only do manual data entry etc.

You may need another step to complete the roundtrip.  Entering the data in the PowerApp visual will not automatically refresh the Power BI data unless your Power BI dataset is direct Query and you have enabled automatic page refresh.  Otherwise you need to manually refresh.

As you probably notice by now this is a klutz, but it's the best klutz we have so far for the data write back.  I sure hope something better than that is on the Power BI roadmap.