All Mastt users start with a Sandbox Project. The Sandbox Project has been filled with example data, and it is not connected to any other projects or programs (by default). Use the Sandbox Project to test out ideas and find out what changes when you add or remove data! It is designed to be a place for you to experiment, without worrying about making any incorrect changes to your projects!
If you would like a new Sandbox Project created, you can submit a Support Ticket through this form here.