wireless connection troubleshooting ubuntu 20.04
rfkill list
#if hard blocked option is yes
lspci -v
#at the Network controller you will find your wifi adapter name
#search on google and download the iwllwifi corresponding at the network controller
#exemple for intel i go to https://www.intel.com/content/www/us/en/support/articles/000005511/wireless.html
#And download iwlwifi-xxxx.tgz
#After unzip and go to the directory with the terminal and copie iwlwifi file in /lib/firmware
cp iwlwifi-xxx /lib/firmware
#After reboot
reboot