Printing directly is still not avaiable so far in PowerApps. But you could vote on below idea, whose status is started:
do you use SharePoint as your datasource? If yes, then an easy and quick solution could be to write a workflow which automatically fill out a word content type (for example a word document).
Just took a quick look at it. Have to leave but look at minute 10:04 on the Youtube video. Its the part where he shows the flow to create the PDF unless I am missing something. I am running out the door so didn't verify it 100% but I believe thats where your looking for.
I recently posted a blog that leverages a Microsoft Word document template with content controls mapped to the Document Library metadata fields. This is similar to the html-based solution mentioned earlier in this thread.