You can change the plan North using the Orientation parameter.
True North is when the plan view is oriented to the real-world north direction.
Project North is a virtual orientation (normally orthogonal to the screen) used to facilitate modelling and understanding the project.
This might be the most intuitive way of working, but it is crucial to represent the actual north for all kinds of documents. Establishing the True North is easy, you need to:
This means that you probably started working using a reference and your plan views are oriented to the real-world north direction.
The manipulation to define a Project North is unfortunately more risky, as it repositions the elements in the model.