Brightness slider removed after new update, can I just have it back? The monitor brightness is causing me eye strain, not even settings can change anything.

This is beyond infuriating, why remove something that I use everyday? Its basic accessibility, I cannot do my assignments or anything else as the brightness is affecting my eye strain. I am not downloading third party software just for this. This is the most BASIC feature a laptop can have. I do not understand why they removed brightness settings, its beyond my brain capacity to understand microsofts process behind this decision.