i'm working on the red zuma project. Do I need to start a new project in Microsoft project for parts 3 and 4?

i'm working on the red zuma project.  Do I need to start a new project in Microsoft project for parts 3 and 4?

I was working on part 2, and went to the gantt sheet to add new info, but the info from part 1 was still there, can I start a fresh gantt chart without losing the data?