Hi, i’m a total newbie to Linux and I have similar problem.
I just installed the latest EndeavourOS with XFCE desktop environtment and my touchpad doesn’t work among other issues.
Here’s the output from the first command you suggest.
I don’t really know how to perform your second suggestion. I tried typing the /etc/default/grub in the terminal but it said “bash: etc/default/grub: No such file or directory”