Hello, thank you for getting in touch!
As ToxicBOI was kind enough to mention, Instanced Properties may only be changed via script, while Properties may be changed by script or through the Material Inspector.
Since you're new to Unity and ASE, you might be interested in checking out both our
Wiki Manual and
Official Youtube channel for tutorials and tips regarding editor use and shader creation.
Feel free to let us know if you have any further questions, we'll be happy to help!