Click the gear icon that's front and center on the Pipeline page.
Only process admins can add stages in the pipeline.
You can easily add new stages to the Pipeline by following these steps:
1- On the Pipeline, locate the edit button (“gear” icon) next to the date, at the center of the pipeline toolbar.
2- Click on the button to go to the pipeline editor page. The page has two columns: the Project Stages list on the left and the Stage Editor on the right.
3- On top of the Project Stages, click on the “+” button to add a new stage.
4- Use the Stage Editor to give it a name and governance/guidance.