Hello.
All the videos I’ve seen use additional hardware for creating music, such as keyboards, guitars, launchpads etc.
Is it possible to create full-fledged music without using these? Or should I seriously think about buying one.
Thanks!
Theoretically you could? If you only work with samples you drag in. And use the chord track and/or input notes with the mouse in the editor(s). But I highly doubt it will suffice. I would at least want to have a simple midi keyboard controller with maybe some basic programmable knobs to make life a lot easier. But IMO you don’t need all the fancy gear you sometimes see on video’s. It can greatly improve your workflow but you have to know how to use the devices by heart. Otherwise it could well slow you down and break your creative flow because you have to think about how to use them all the time? 
I would think it depends a lot on the kind of music you’re wanting to create?
Obviously anything with live instruments will require an audio interface of some sort, possibly also a microphone plus the “real” instruments.
Virtual instruments can be input just using the mouse and computer ( I do sometimes when out with just a LapTop) but I think most users find it easier with a piano style keyboard. As mentioned above if you get one with a few knobs and buttons it may help you, too.