I recently got a ThinkPad E-14 Gen 2 with AMD Ryzen 5 and installed Ubuntu onto it only to realize that the function keys do not work at all. And I came to know that Lenovo does not certify the E series for Linux, so that was a bummer.
So, reading about the issue I came to know that the function keys starts working after the laptop has been suspended once, so I made this hack to make it seamless
The solution Link to heading
Open your crontab
sudo crontab -e
This will ask you to choose your favourite text editor, choose the one that you know. Add the following to the end of the file
# Fn key fix
@reboot sudo rtcwake -m mem -s 2
Save it and exit out of the editor. So what we are doing is, we are asking the system to suspend for 2 seconds after every reboot. This fixes our issue without us even noticing.
You can either reboot your system now and test it or just run sudo rtcwake -m mem -s 2 from the terminal to have your Fn keys work immediately. Once rebooted, you don’t have to worry about it at all