Don't hesitate or overthink it. Just dive headfirst into it. The day you start is the best moment. The thing you chose to do, is the best.

Learn by playing around. Play to your strengths. Dabble with coding, sound, graphics, mechanics, and figure out what gets the fire going. Feed that fire.

When you've had a bit of taste, try to complete a small simple project. This is surprisingly difficult! Learn to remove features and complexity, simplifying until you can actually finish the game.