You can get any information from any guest that came to your property (or will come! )
To do this, you would want to go to Menu > Profiles > Customer Profiles.
Change the Mode to Created to capture all profiles created in your system.
Select all Status as well as the according dates (When the hotel was opened for example)
View report function may take a bit more time to load as it may contain a lot of information. We recommend that you export them instead.
Once the export stops processing, a notification will let you know that it is ready!
You can then open it in Excel or whichever tool you use and analyze or filter all relevant information, ei.: your client's email and whether or not they agreed to receive marketing emails.