How Do I Import a Project Into Unity 3D?

To import a project into Unity 3D, you typically open an existing project file using the Unity Hub.

Here is the process, based on the provided reference:

Steps to Open an Existing Project in Unity Hub

If you have a project saved on your machine that you want to work on and add to your Unity Hub list, follow these simple steps:

1. Launch the Unity Hub. This is the central application for managing your Unity projects and installations.
2. In the Unity Hub interface, locate and click the "Projects" tab. Within the Projects tab, click the "Open" button.
3. A file explorer window will appear. Locate the project you need to add by navigating to its saved location on your machine. Once found, select the project folder (or the project.unity file within it, depending on your operating system and Unity version's file explorer behavior, but typically you select the root project folder) and click Open.
4. The project will immediately open in the Unity Editor and will be added to the list of projects displayed in the Unity Hub.

This process effectively "imports" or adds an existing Unity project folder from your file system into the Unity Hub's management list and opens it for editing.