After Installation, Open a New Project
Goto "File" in Unity menu and click "Build Setting"
Click on "Android " and Press "Switch Platform" button
Goto "Window" tab and Open Package Manager
In Search Box, write "AR Foundation"
Selection 3.0.1 and click install
In Search Box, write "ARCore XR Plugin"
Selection 3.1.4 and click install
Goto "Edit" tab in unity menu and click "Project Setting"
In "Project setting" dialog box click "AR Build setting" and Press "Create"
In the new dialog box, click "Save"
Your installation process is done here.
Few other things to do
In the player setting, in "other setting"; choose Minimum "API level 24"
Here you Go. All is done.
You can now Add AR Session
Adding AR plane
Here all is ready. you can start working with your AR app.