with mime mail you can send an HTML page as mail.
Not simple, but possible.
Search for MMAIL here.
If anything but text is involved, you’re going to have to convert to “real” e-mail and leave SNDDST behind. That is a stop-gap measure anyway and should have been discarded years ago.
Install a utility such as MMAIL or create your own. If you do it yourself, you might use the QtmmSendMail API to associate MIME attachments with an e-mail message. You’ll need to know how to create a MIME attachment and how to structure an e-mail body properly.
The decision to build, buy or install a downloaded utility is up to you.