@xiuyu song ... I understand where you are coming from
I believe as with many, that Linux lets itself down a lot in terms of lack of documentation readily accessible to the User, and in particular, the newcomer (newbie, noob), of which I still consider myself one after nearly 6 years.
With my Debian-based Distros, I usually leave the Welcome screen checked to show at startup, because it provides a quick point and click option for eg Documentation and Forums. In Manjaro (Arch-based) it is the "Hello" window, likewise.
For all the wonderful diversity of Linux, the existence of or splitting into "Families" can be daunting and confusing to many, with different protocols used, and different Terminal (CLI) commands between Debian-based, RPM-based, Arch-based, Gentoo-based, Slackware-based and on and on.
Just look at commands for downloading let alone installing, and we have aptitude, apt, apt-get, yum, dnf, zypper, urpmi ... and again, on and on.
The overused and nebulous "they" (most often the Linux Developers) don't do themselves a lot of favours to recruit people to our FOSS cause.
I truly think "they" should have a big think-fest once a year, perhaps two years, where they come together and try to engineer similarities instead of nurturing differences they believe make them stand out from the rest of the pack.
But this is a rant and verging Off (your) Topic, so back to business.
I note from your reference to "yum update" that you are using an RPM-based Distro, and likely one that has not yet deprecated yum in favour of DNF. For The Viewers, "yum" is the Yellowdog Update Modifier", and its likely successor DNF is "
Da
Ndi
Fied yum".
If you let us know what Linux you are using, down to the version number and dot-point release (or rolling) and desktop environment (DE) ... eg I am writing this from my Manjaro 'Gellivara' 17.0.6 64-bit with the GNOME DE ... we might have some more input from people with ideas for you?
I would like to spend more time on this issue, but I have a number of "babies to put to bed", with an upcoming Tutorial on Timeshift for which I have completed 70% of the textual instructions and one out of three Youtube videos. And then 2 more commitments I have triaged. I get sidetracked easily (Adult ADD/ADHD) and I am trying to get organised.
Bear in mind too that there are frequent new developments by key figures within the industry, and one that springs to mind was MATE (pron. "mar-tay" after a South American tea-like beverage). It was authored by a fellow known as "Perberos" from Rio Negro, Argentina. He was an Arch user who was not happy with the way GNOME 2 was headed towards GNOME 3.
So let's keep our eyes and ears open for new goodies, and if you have not already bookmarked DistroWatch, do yourself a favour.
https://distrowatch.com/
Cheers for now
Wizard