Big sur

Tried to update my laptop to big sur and keeps getting stuck on less than a minute remaining. I’ve tried restarting it with safe mode, recovery mode and reset NVRAM. Recovery mode just stayed on a black screen and the other 2 took me back to the less than a minute remaining screen once I logged in.

I have also been having other issues as for months my Mac has been running slowly and the fan only goes off when I close the laptop. It also does not charge when I plug it into the charger it says it’s charging but the percentage does not change and there is no light on the actual charger.