As someone that loves to draw: definitely worth it. Is it worth it for you? I can’t tell you. Having a clear goal helps tremendously so wanting to create your own comic can be good motivation.

As for how long it’ll take you: depends completely on what your own measure is. The more you practice the better you’ll get. Also: set goals for practice (I want to learn hands, I want to draw clothes etc.)

And: drawing is a rather inexpensive hobby to get started, if you don’t like it, you can just quit whenever.