If you want to install Ubuntu 20.04 LTS on the Lenovo IdeaPad 3. You have to fix the trackpad for the mouse pad.
Out of the box, it doesn't work.
1. Open Terminal and edit the Grub file (comment out the file and then make the change)
vi /etc/default/grub (if you want to use another editor...go for it. I'm a vim guy.)
2. sudo update-grub
3. Reboot the computer. After you get to the login screen, you will see your mouse pad working.
(No luck on the brightness keys on F keys).