Can I embed the PDF into the auto-respond email, as opposed to making it an attachment?

Can I embed the PDF (generated from the user filling out a Form on my site) into the auto-respond email that the user gets, as opposed to making it an attachment?

Technically that's possible but the PDF would become useless when opened on email since email clients do not support embedded PDFs. It's either the PDF would appear blank, an attachment or it would be removed. So your only option is to attach the PDF.

Thanks