With LeadBI you can create an automation from an Opt In Form Submitted, for example add an event, a Webinar in which all the users can subscribe. Insert the name, select the Trigger “Opt In Form Submitted ” from which the automation get started, the maximum number of times this automation can execute for contact, the conditions (optional) and continue.
Now you start to build your Workflow and decide the actions you want to set up. In this case you can assign tag attributed to user, by clicking on actions.
Once the tag is assigned, set up an email to send to the user, to confirm the webinar subscription.
So, you have set up the automation!