Domains
Own domains come with Premium. On Plan & billing, enter your domain (for example www.yourbusiness.com), then in your domain provider's DNS settings add a CNAME record for www pointing to the address shown there. Press Check DNS; the secure padlock is set up automatically.
Your main website and email can stay where they are: you can use a subdomain like offers.yourbusiness.com.
Still need help? Raise a ticket.