Reaper

No, but I had heard very good things about it. Given that I am not very up to date on the subject, isn't the software a bit outdated?

On the contrary, at least for me, I am using it these days because I am trying to make music with different software and VSTs simultaneously, precisely to pave the way for different approaches.

It is a software that is not very easy to understand and allows you to do many things; moreover, it supports external editors and I will try to use MuseScore (which is indeed the notation editor supported at the moment, or so it seems).

Paradoxically, the most common commands are also the most "messy"; for example, in my case, I only had to copy patterns from a MIDI track, but the program also copied the portion of the sequencer that included other tracks. So, I asked for advice and it "turned out" that I should have pressed Alt and dragged the desired portion with the mouse, copying it several times; everything was fine, except that sometimes you have to work backwards, meaning by copying portions of all the tracks that make up the piece multiple times (inevitably, dragging ends up bringing along the others as well), then going back to delete the portions we don't need.

A bit too cumbersome, but I imagine it's just me having these difficulties, because as far as software goes, it seems to offer many functions.

As soon as I finish a piece, I will publish it; I am trying to write one that has sounds reminiscent of 70s/80s synthesizers, especially using VSTs (I used Reason and still use it since 2002), something I have never done before.

But is it a notation program or something else? Sorry for the question, but I knew it as an "alternative" program to Logic, Cubase and so on

It is as you say, but they have developed a plugin that allows the MIDI file created with it to be processed using MuseScore.

I still have to try this function, but from some enthusiastic comments on an English forum, in theory it seems that it can (in this way) support score writing.

As soon as I try this feature, I will let you know.

So, I still can't use Musescore in "live" with Reaper, but on the other hand, I finished a piece with the latter.

I'm understanding how to use it and after all it doesn't seem too complicated; like everything else, even if it goes without saying, you just need to practice.

I usually don't read manuals, I'm someone who needs practice.

I've seen some tutorials on the internet, but (at least those I've seen) I don't think I've seen any where the steps for working in MIDI are explained chronologically, so

maybe (if I feel like it) I will make a small tutorial about it, just with the basic notions to prepare a piece with the creation of MIDI tracks, importing VSTs, assigning effects, converting them into audio tracks, and exporting the piece in MIDI format as well as in audio format.