ARKit provides a framework to display 3D text in real world using augmented reality. This video explains the same:
Is there a similar mechanism to do the same using Unity and Vuforia augmented reality support??
I tried displaying 3D text, but it simply gets rendered as a 2D text.
You can do this with the standard UI Text component. Use BaseMeshEffect to obtain the Mesh and vertices of the Text component then extrude it outwards. You now how have a 3D Object. You may need to change the material to standard material.
If you can't implement this then use an existing plugin. The Simple Helvetica plugin can do this and it's free on the assetstore.