How can I add a collaborator/would they be notified when I am notified of form entries?

You may add a collaborator in your Form builder.

Kindly check this guide:https://www.jotform.com/help/419-Understanding-Form-Collaboration

Unfortunately, the collaborator is not notified when your form is submitted unless you add them as an email recipient.

Do note that only paid users can have multiple recipients for notification/autoresponder emails.

Guide:https://www.jotform.com/help/39-Send-Notifications-to-Multiple-Recipients

Hope this information helps.