Keep in mind there's nothing requiring anyone here to write a story, you can contribute a lot to the community just by reading or reviewing or getting involved on the forums. Honestly, I'd never recommend anyone write anything just because they felt like they had to. If you're not feeling inspired at all and you're just forcing yourself to go along, you won't enjoy anything about the experience and the final product will be lacking.
That said, if you're dead set on this, maybe you could practice with a regular short story first? All the things necessary to a linear story are necessary to a CYOA, but a linear story is much simpler to actually write and will give you a good sense for things like plot, characters, pacing and so on before you try to tackle the more complicated issue of how to structure the branches and the sheer of amount of extra work required for a CYOA.