step 1 : Hit the Windows key, and then type in “Power Options” into the search,
step 2 :which will pull up the Power Options panel. Once here, step 3 :click the “Change plan settings” link on the selected plan.
Step 4 :Then click the “Change advanced power settings” link.
In the Windows search type in Power Options. In the Power Options click Change plan settings next to the selected power plan. At the bottom click on Change advanced power settings. Scroll down to Display > Enable adaptive brightness. You'll have the option for the brightness adjustment while being plugged in and running on battery. Select Off from the dropdown for the one or both that you want to disable. Click Apply and OK.