Hi @Crystal_Hopper,
To your first question:
Yes SMS can be build into contact-based workflows. You can add the form submission as the workflow trigger and use the new ‘Send SMS message’ action to send their automated message. One callout is that you’ll need to ensure that the form is using/capturing the same phone number property that will eventually be used in the SMS and make sure to have validation enabled to capture phone numbers in the right format (with a +1).
To your second question:
This information is available on the post send page of the SMS. Any messages sent, but not delivered will be surfaced in the ‘Not delivered’ tab of recipients. We do not pre-validate if a number is a landline, as some carriers convert SMS into voice messages when being sent to a landline.