Do it for the fun of doing it.
Begin with the part that you enjoy the most, be it graphics, programming or music. Choose some tools you want to learn, it is more rewarding than using tools you already know. Work on your project bit by bit, your first iteration will be weird prototypes. After some time the prototype will become somewhat playable, then pretty decent to finally be a full featured game. Just never forget that the goal is not the finished game, it is to enjoy making it.
I wish you all the best in your gamedev journey