Start small, with something that can get you familiar with coding. Don’t aim for a publishable work straight away. If you do, there’s a high chance to get burned out before the end. Interactive games take a lot of work you don’t see on a single playthrough because of the choices made by the player along the way. Don’t worry about genre too much yet. By experimenting with small projects like this first you’ll have a much better grasp on what suits you by the time you get to your first big project.
If you’d like feedback on your practice projects, try posting them on the workshop thread.
(My first ever WiP was wiped from the Internet when Dropbox stopped being useable to host ChoiceScript, thankfully. It was over-ambitious in concept, and the writing was horrible.)
Contests or game jams are also great ways to gain experience. Don’t think there are any planned before the next Halloween, though.