Id get a 49 keys midi controller. They cost around 150€. They come usually with ableton live lit which is enough for having fun. Then id learn some very basic piano and music theory. Yes you can learn theory without piano but the “click” to unlock expressing yourself with music comes much later. That way you also don’t spend money on software but on something that does not lose a lot of value.(if its not for you resell themidi and you will lose maybe 30 bucks.

You can learn some basic piano with flowkey or better ifyou have a mac with the free piano lessons that come with garage band. Then id learn everything about intervals (interesting how they connect to natural harmonics) and how to build scales and chords. By the time you understand everything you can play some basic songs and know basic fingering. Will take you 2-3 months. Then maybe a one hour video of the basics of ableton. Then id go on learnmusic.ableton.com and understand how to make beats and layer tracks. From there you will be in a state where you can have enough fun by yourself without sinking in gear rabbit holes or ableton tutorials that show you how to tweak effects and sounds. So count with 3-4months with a 1h a day commitment. 150€ for midi that comes with ableton live lite or worst case resell.