Set up Visual Voicemail. If your carrier supports Visual Voicemail, you can set it up with these steps: Go to the Phone app, then tap the Voicemail tab. Tap Set Up Now. Create a voicemail password, then tap Done. Enter your password again to confirm it, then tap Done. Select Custom or Default. If you choose Custom, you can record a new greeting.
In an ideal world, voicemail would be unnecessary. There would always be someone available to take customer calls and no one would complain about their calls not being returned and/or rejected. But of course, this perfect world isn’t possible. That’s why it’s important to give your callers options when you are unavailable. For example, aside from leaving a message, callers can also choose to listen to some relevant information about your business (such as a list of your services, your address, directions, hours of operation, and more).

There is no definitive answer here, but you should include one of the two at the beginning of your message based on what makes the most sense.
Before you record a professional voicemail greeting, you may want to consider the type of people who might call your home or business. That way, you can think about the information these callers might need before you compose your greeting. Most callers are familiar with how to leave a voice message, so try to avoid giving them instructions. Some things you may want to include in your greeting might be your full name, title, name of your company, and an alternate method of reaching you. If you plan to be unavailable for some time, it can be a good idea to tell your callers when you will return and give them the name and phone number of another individual to call in the event they need immediate assistance. A private voicemail box enables a person to receive telephone messages when the phone cannot be answered.