Hey there!
First things first, let's talk about our git workflow. We have a main branch, and a dev branch. Those are our main branches. The dev branch is always AHEAD or AT THE SAME LEVEL as the main branch. Never forget that!
When we want to work on a new feature (which is the case for you), we start by creating a branch (from the dev branch). We'd prefer if you call it something like feature/your-feature-name.
Just start the app, and you're good to go. But don't forget to start the backend too.