I just did exactly what comes out in the video but the problem still continues, when the apple logo appears the brightness is lost, and after about 7 minutes it is fixed, I also wanted to ask about the audio kext and also about whether there is some way so that the laptop does not rise so much its temperature?Thanks for patience! You should try hotpatch for your brightness, this is pretty simple, better follow video attached below. That should enable you to adjust brightness from System Prefs > Display Settings, but not from keyboard Fn+ Brightness keys if you have brightness keys assigned more form F9 then you'll need an extra patch for that. Till now I guess you should also be able to adjust brightness from Fn+B and Fn+S or similar keys. You can find the patching brightness keys in our forums.
edit: (I also realized that I can not change the brightness from the settings, even if it goes up or down, it does not change anything) (I also noticed that the keys that raise and lower the brightness are (+ brightness = pause / inter) and (- brightness = F12)