From the home page click on the green new project button.This will focus you into naming a new project inside your existing projects list.Once named, the project will get asssigned an id. Once that id is ready you can click on that element to load in the project.
From here you can begin any kind of modeling task. Go to the chat window at the bottom and try asking Davinci to build a simple parts tree. Once submitted the task will be started.
On task compelete you will see new objects populated in the mode index pane (on the left side of the window). You can either interact directly by clicking on objects in the index or you can click on the View button in the chat response to see a change log of the AI modifications.Happy modeling!