How brightness change acer laptop without function key

cut and paste from Microsoft

To turn adaptive brightness on or off

1.Open Power Options by clicking the Start button , clicking Control Panel, clicking System and Security, and then clicking Power Options.

2.Under any plan, click Change plan settings.

3.Click Change advanced power settings.

4.In the list, expand Display, and then expand Enable adaptive brightness.

5.To turn adaptive brightness on or off when your computer is running on battery power, click On battery, and then, in the list, click On or Off.

6.To turn adaptive brightness on or off when your computer is plugged into an outlet, click Plugged in, and then, in the list, click On or Off.

7. Click Apply. Click OK.