We recommended to reserve a domain name in your business name. If your domain name is taken by any domain reserving company or a competitor, it could be difficult to establish your brand and continue the business without a proper website. (example: www.yourbusinessname.ca)
An Business Email Address is the one that has your business name in it, and will be used for business communications that is based on your custom domain. (example: CustomName@companyname.com)