You can create multiple boards in the same project by creating your board and saving it to your specified project folder. You can create project folders within your Profile by following these steps, or create a new project folder in the editor program
Step 1: finish your board
Step 2: Save it in your desired project folder or create a new folder
Step 3: Go back into your profile to view your list of projects.
Step 4: You will find all your multiple boards saved in this specified project folder