Changes I do in my instance editor won't show up on the level editor

I’m really new with unreal engine (started 2 days ago) but I’m striving to learn how everything works. Until now, I always saved any material changes by saving, and waiting for the changes to load for a while. I found out that by creating a scalar parameter though, you are able to quickly change between different values and get the results on your level editor instantly.

I’ve been trying to do this with my roughness value, but any changes I do to the value doesn’t show up on the level editor, but only on the “Instance editor” if you know what I mean. It’s like they aren’t connected at all to eachother. Is there a common reason for this? Please share your knowledge to a newcomer :3

Thanks!