The best FOSS software for producing music?

In the past when I had Windows I was making beats in FL Studio and sometimes mix in Reaper. I didn't have advanced skills but I knew how to use the…

Have you considered LMMS? I think it’s exactly what you’re looking for. Extensive manual, free, open source, made for Linux, focuses on doing the basics well
Interface Overview | User manual

Yes, but I heard bad opions about it in the past, don’t remember where. Are you using it?
I haven’t used it but have heard good things in the past year or two.

I’m not using it but since it’s free you might as well give it a go. I’ve heard excellent things about Bitwig in Linux and even took it for a spin. It was nice, but no better than on Windows.

Myself, I used to use Reason on Windows, these days I’m DAWless mostly.

It’s very much easier to use than ardour. Makes it very simple to open the piano roll and draw in some midi notes. Includes a decent amount of default samples and presets. It was good for no-nothing-hobbyist use case. Between tutorials and the manual, pretty figure-out-able.

Ardour by contrast seems more focused on recording live instruments. I’m sure it’s high quality stuff, but trying to do basic things just feels obtuse.

If you are coming from FL it leaves a lot to be desired, but it’s the most similar I’ve seen. Definitely worth a try.