To start a project, press the button ▶︎| (or Shift+Enter), paying attention to the cursor: it has to be in the cell below.

Projects you can choose:

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  • To launch a new projet use again the ▶︎| button (or Shift+Enter), but only after restarting the kernel with the ⟳ button. Choosing Kernel/Restart & Clear Output you also have a clean restart.