When you say "make," do you mean cutting/editing music that already exists, or do you mean eriting/producing your own music from scratch?
For the former, I'd recommend Audacity, which is free. A bit of advice: learn the hotkeys for zooming in and out, because that will make your workflow much easier and faster.
If you're looking to compose and produce original music... well, I recommend Reaper (which is not technically "free," but which has an unlimited free trial), and depending on what instruments you want to use I can recommend some decent free or cheap virtual instruments and effects.... but please understand that producing your own music -- while loads of fun -- has a steep learning curve, and is the sort of thing you can expect to spend months or years learning before you really get comfortable with it.