If your laptop or keyboard has backlighting built in, you don’t need to search for a power switch. Simply turn on the lights whenever you’d like.
When they discover that their laptop’s keyboard light switch isn’t actually a switch at all, many laptop owners are frequently unhappy. Your keyboard’s lights are actually integrated into the circuit board, and all you have to do to switch them on and off is press the keyboard’s button.
Keyboards do not all light up. Some manufacturers only include it as an optional extra on their entry-level laptops, or they don’t provide it at all. You will have to utilize your tablet or smartphone in place of your laptop if your low-end laptop lacks this capability.

How to Turn On the Keyboard Light On Windows Computers
You are probably aware that your keyboard typically has an F2 or F12 key if you use a Windows computer. The keyboard light can be turned on or off using these keys.
You can check out this collection of different keyboard shortcuts.
But not every Windows computer will respond to the same key in the same way. While some PCs use the SHIFT key as the light switch, others use the CTRL key.
There are various situations in which the F1 key is employed. The key is used to quickly cycle across the keyboard when typing, and it also activates the in-game help menu when you’re playing games.
One of the four unique function keys—F1, F2, F3, and F4—is most likely used by your regular keyboard to illuminate the indicator rows.
On a keyboard, there are several ways to adjust the lighting. You can select Keyboard or Accessibility from the Control Panel if you’re using Windows or Mac OS X.
Under the Display Settings menu, you’ll see the backlight off option.
You can execute sudo xbacklight -set 100 in a terminal window when using Ubuntu Linux.
Also see How to use the keyboard to copy and paste in Windows.
What if a Windows Keyboard Light Won’t Turn On?
Keyboard Settings and Display Settings are the two options you’ll find in the Settings/Ease of Access menu. When you select Display Settings, the Display panel will show up.
The Keyboard Settings panel will appear when you click on the keyboard icon. Click the “Adjust keyboard” link located in the upper left corner of the keyboard panel if the keyboard is not functioning properly.
If your keyboard isn’t working, try the following simple troubleshooting steps:
Verify that the power cord is correctly plugged in and attached.
2) Launch the Device Manager.
3) To enlarge each area, click +.
4) Verify that the status of your keyboard is set to “working” and that it appears under “Keyboards and pointing devices.”
5) If you’re still having trouble, contact your keyboard manufacturer or call tech support for instructions.

How to Turn on the Keyboard Light on a Mac
It is true that many consumers of Apple, including those who own MacBooks, are unaware of this capability, and it is also true that many people who are unfamiliar with Apple goods would find it difficult to utilize.
The Apple blog provides a comprehensive explanation on it, including instructions for turning on the Mac’s keyboard backlight step-by-step.
They merely think they can utilize the Touch Bar since they see a big, colorful button with an icon for brightness.
You must hit the button and choose Increase Brightness to overcome this presumption. The brightness slider will then be visible on the bar.
Conclusion
The exception is when a Touch Bar is present instead of Mac function keys; in that case, the Touch Bar controls the keyboard light.
The keyboard backlight controls on Macs and MacBooks are located at the right side of the keyboard, above the F keys.
FAQ's
If your keyboard backlight is sensor-activated, and it doesn’t work anymore, there’s a chance an outdated or corrupt driver is causing the problem. To fix it, you should update your keyboard driver.
You might need to press and hold the Fn key while pressing the backlight key. If your backlight won’t turn on or stay on, change the “Action Keys Mode” or timeout setting in BIOS. If your keyboard backlight isn’t working, hard reboot your HP laptop by removing the external battery while the computer is powered down.
In some cases, if your laptop has the right keyboard light buttons and they still don’t work the way they’re supposed to, it’s possible that you may need to check your device’s BIOS settings and make sure that they’re configured correctly, or your BIOS may need to be updated to the latest version removing the external battery while the computer is powered down.
Does keyboard backlight drain battery? A backlit keyboard typically uses a low amount of power and will not have a significant effect on your laptop’s battery life. However, if you are using a gaming laptop with adjustable brightness settings, then having the backlight set to high levels may decrease your battery life.
If they are available, they can enable the backlit by pressing FN and F4 keys (FN+F4 keys) at the same time. Pressing the FN+F4 keys continuously increases the brightness of the keyboard backlight; while pressing the FN+F3 keys continuously decreases the brightness and ultimately disables the backlight