Can the software send my customers a reminder before they travel so I do not have to remember to do it myself?

Yes, in most cases it can. Reminder messages are usually handled by automatic email templates that are linked to the travel date on each booking. You set up the wording once, choose how far ahead of departure it should go out, and the system sends it on its own using the details already held against that booking, such as the passenger name, the hotel or flight, and the dates. The message goes out under your own agency name and branding, so your customer sees it as coming from you.

The reminder can only use information that is actually in the system, so bookings you made over the phone or direct with a supplier need to be entered into the software first, otherwise no reminder will be created for them. It also helps to keep customer email addresses accurate, because a message sent to an old address will simply fail quietly. Some automatic emails can land in a customer's spam folder, which is worth testing with your own address before you rely on it for every booking.

Text message or messaging app reminders are a different matter. Those usually need a separate messaging account of your own, and whether they are included depends on your plan and on which messaging service you want to use, so that is something to confirm rather than assume. Reminders are also not the same thing as supplier change alerts, which work separately.

The best next step is to check which automatic emails your plan includes, then send yourself a test booking reminder so you can see the wording and timing before your customers do.