Hi Raja,

By default, a new project starts in the sandbox. That's a easy way for PoC's and developing a first idea.

For the full blown DTAP-street, you need to buy a license. This can be on different clouds, but using Mendix Cloud is the most easy way. See more about pricing and buying a license here.

If you have Mendix Cloud resources, you can unlink your existing project from the Sandbox environment, like described above. You will loose the data in this environment, but then can link it to your licensed cloud nodes.

Hopefully this helps!

Johan