Most of the time, the Asset packages you use in Unity come directly from the Asset Store, and you import them in the Package Manager window. However, if you have a
.unitypackage file saved locally, for example, because you created your own custom Asset package, you can import it into your project in the Unity Editor through the Assets menu.
To import a local Asset package in Unity:
Open the project in the Editor where you want to import the Asset package.
Choose Assets > Import Package > Custom Package. A file browser appears, prompting you to locate the
In the file browser, select the file you want to import and click Open.
The Import Unity Package window displays all the items in the package already selected, ready to install.
Deselect any items you don’t want to import and click Import. Unity puts the contents of the imported Asset package into the
Assets folder, so that you can access them from your Project window.