If you want to add the checkbox in your form while your subscriber wants to subscribe to your newsletters. Then you add the check as per your requirement.
For this how to add the checkbox in your form, follow the steps below,
Step 1:- Login to your MailPion account.
Step 2:- Click on Email List>>List>>click on the existing list.
Step 3:- Click on Custom Field.
Step 4:- Click on Add Checkbox.
Step 5:- Add the checkbox field from here.
Step 6:- Once add the check box in the form, the form will be like this.
Step 7:- Once your subscriber subscribes or fills out the form, that subscriber will be added to your list.