Oh. I mean, why do you think you need to get familiar with Debian first then Devuan? Why not just use it directly, if your target is Devuan?
Judging from your question, I think you have not even touched them at all (if you have attempted to try them, your question will be different and more specific, like what doesn't work etc).
Debian/Devuan and both are convenient and easy to install(https://www.devuan.org/os/documentation/install-guides/chimaera/install-devuan) or use, with their desktop ISO. You don't even need to know Unix commands to finish the install, and I think the only things that might get you lost after the installation are, adding your user to sudoers (with things like visudo with root), and editing the repositories list (https://www.devuan.org/os/packages).
Anyway, the only way to get familiar with anything is to use them. Without trying them you never know what you don't know. There is almost no cost trying the distros. You can always experience them first like in a VM, or with a live USB or a installation on external drives to test the hardware compatibility.
Btw, how should I ask that in Japanese? (about my previous reply)
Okay,thanks. Well actually I did install Devuan in the other my sub laptop so don't worry.
Well I didn't catch your intention or what did you ask to me but I'll try to explain that.
And also you should ask like this.
わざわざDebianを慣れるからDevuanをインストール必要はないと思います。
わざわざ➜take trouble 慣れるから➜you can get the used to 〇〇
My brain: What!?
And 慣れる is very complex phrase to this sentence,so I will chance like this
”わざわざDevuanを学ぶために、Debianをインストールする必要はないと思います”。
(You don’t need to take the trouble to learn Debian。if you wanna learn about Devuan. you should use and learn on Devuan then you don’t need to install Debian)
Oh, maybe it was about the wrong tense that got you confused? (so 慣れた?) The meaning are the same as what I expected.
The meaning I wanted to express is:
"Debian, Devuan, I think either one is ok, but you don't need to (take the trouble to) get used to Debian then to install Devuan. If you have any fear it is more practical to try them first in VM."