Hello lessassy_3869 and thanks for reaching out to us through our community forum.
Giving it a quick try I can see that actually Sharepoint does not accept PDF files, I'm not sure if it's a matter of my environment but when I try to upload a PDF file it says it's not supported and I should use OneDrive instead to upload PDFs.
Either way, once you have the PDF uploaded (or any other file), you can use the block to get the file. Sharepoint endpoint has one called "Get Item".
After this block, you use the only Mail block available "Send mail". In the connection you should fill in your SMTP settings and in order to send the file you choose under the "Type" field the item retrieved from the "Get Item" block mentioned previously.
Find here attached a very simple example of how the workflow can be
We hope this helps, let us know if we can help with anything else.
Regards,
Pedro
