The Project page lists all the projects that your account has worked on.

You can create a new Site by selecting the +Site button, Join a Site using a commissioning code, and change the sorting order of the Sites on the list.

You can enter any Site by tapping on a card, but are only able to edit the ones you currently have access to.

Sites will sometimes have a status depending on if you have accessed it using a commissioning code, or if you have completed your work by doing a handover for example.