How to soft a laptop screen?

Sometimes it may well show a star like symbol, but it shares alike button as another button. With mine, it shares with the arrow button, but if I wring the arrow button, it wont relocate lighting, so you must press the "fn" central (location on the device) When you press the fn key, it will let you operate the other locale thereon toggle. It is not like pressing shift with the number keys to get symbols
Also, sometimes, the F keys (F1, F2, etc) can be used to set lighting.
Likewise, if you know how to get into BIOS, there should be a scene to change it.