Lenovo IdeaPad-3-15IIL05 No touchpad

[WytWun]

Have you tried booting any live distros (without installing) other than Lite via USB to see whether the touchpad works?  It might be useful to try some outside the Ubuntu family, e.g. Manjaro, Mageia, Fedora, SUSE.  If you encounter any where the touchpad works, you might be able to identify drivers or kernel options with the live image running.  I say "might" because it might be effort for nothing too based on a prior experience...