A. The Next Step is showing the next cued up task to be performed with/for this contact record.  If no next step scheduled is displayed this means there is no future to-do items scheduled for this contact.  To change this, click on New Task and set a task into the future, perhaps schedule a call, set a reminder to send an email etc.

Setting up a to-do into the future will automatically populate the Next Step scheduled on the contact record’s summary and displayed as an Assistant Prompt or Next Step Needed on the Today dashboard: