To get started with Firebase, you will need to sign up and log in using their website: https://firebase.google.com/.
Go to the Firebase console (by clicking on GO TO CONSOLE), and then click on the Add project button:
You will then be asked some details, after which your new project should be created (and show up in this panel, such as the sensor-project project that is already created)
You can explore your project's console and take a look at the various features and add-ons that Firebase provides: