You can add more email boxes anytime. You get 15 email boxes that come with your plan. If you need more than 15, you can request more for a fee.
Good job, you now have company email for a one-time fee.
*Note: email deliverability is controlled by the receivers spam settings. If someone sets their spam filters to be “high”, even valid emails you send may get caught in their spam filter. If someone has trouble getting emails from you, they can “whitelist” your emails to ensure deliverability. If you have any questions, simply submit a ticket here.