Note: you must be on Sendspark Pro or a higher plan to use Video CTAs.
Follow these steps to add your calendar link to your video:
Toggle on the Call-to-Action field
Write your desired button text (ex: Schedule a Meeting)
Add your calendar link (from Calendly, Hubspot, Undock, etc.) in the URL field
You'll be able to check that everything looks good in the preview area on the right of your page 👍