Why is my laptop screen flickering?

It seems that this laptop is having this issue across the board. Thankfully, that means others have been diagnosing the problem. Here are some fixes that have been proposed:

1. Changing the refresh rate in the settings. In order to access this going into Windows Settings, then go to display, once there head over to advanced display settings, after clicking on it, click on Display adapter properties a small window will appear click in monitor and once you click it open up the refresh rate and lower it to 60hz and make sure you click apply, now all you have to do is reset your laptop.
2. Updating your drivers. In order to determine whether or not it's a driver issue, open up task manager, and if it flickers with the laptop, then it's a driver issue. If not, the next suggestion will be for you. Once you've done that and it does flicker with the task manager, then right-click on the start menu and select Device Manager. Afterward, find Display adapters and expand it, then right click on the driver and select Update driver. Now, once you click it, select either Search automatically for updated driver software or download the latest driver from the manufacturers website. Once that is done, reset the laptop and check for flicker.
3. If the Task Manager doesn't flicker, that could mean that a third-party application you recently downloaded could be affecting it. A good way to check would be to boot up the laptop in safe mode to see if the flicker continues. If it doesn't, then it's more than likely an application. In that case, uninstall any recent apps to see if that fixes it.
4. If the first three options didn't work, this could be an issue with the BIOS being outdated if thats the case, then this link will help you with updating the BIOS. https://www.asus.com/me-en/support/FAQ/1...

Hopefully, one of these options will work for you. If not, come on back, and we'll look into it some more!

Well in most of the case an outdated display driver cause this issue. So I will suggest you to update your display driver it can fix the issue.

The problem was my wifi driver.. update your driver from asus website.. to test if its your wifi, turn off your wifi from your laptop and the flickering should instantly stop.