Hi @lknudson2 ,
Could you please share more about your scenario? Do you want to send Email to current user of the App with attachment of a PDF file which is shown in the PDF reader control when associated record has been selected? Do all users have the O365 Exchange online license?
If all users have the O365 Exchange online license, you could use a Office365Outlook.SendEmail method to let user send an Email to itself with the PDF filed attached.
I made a test on my side:
- Add Office365Outlook connector into data sources.
- I added a Dropdown Box named Dropdown1 and set its Items to the Entity which holds the PDF files as attachments.
- Using the Pdf Viewer Control, and set its Document property to below and the PDF file is shown in the control
First(LookUp(EntityName,FieldName=Dropdown1.Selected.FieldName).'{Attachments}').Value

4. At last, I added a button with its OnSelect set to:
Office365Outlook.SendEmailV2(User().Email,"Subject","Body",{Attachments:AddColumns(Dropdown1.Selected.Attachments,"Name", DisplayName, "ContentBytes", Value, "@odata.type", "")})
Received an Email with PDF file attachment after clicking the Button:

You could reference to below link to catch the whole steps:
https://powerusers.microsoft.com/t5/Webinars-and-Video-Gallery/Send-email-with-multiple-attachments/m-p/120193
Best regards,
Community Support Team _ Jeffer Ni
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