Where already above I had to open my laptop to get the fan because there has been a piece of plastic inside since I closed it, only a few keys on the keyboard (5 or so) are working now the question of whether the keyboard is only gone or whether the complete laptop is gone
Probably just the ribbon cable of the keyboard is not correctly connected. Open again and plug in the cable again.
I've already done / tried
If you haven't broken anything when opening it, it can only be due to the cable.
OK thanks