Short Answer Join a Team making games from the ground up.
Medium Answer It depends on: 1) The Kind of Game you want to make? The Art Style? How much work you want to do yourself. I would say that Animation is greatly under estimated when getting involved with 3D game dev, assuming its needed in the first place. Start with Animation.
Long Answer It’s easy to under estimate the requirements of game development. I learned programming/scripting firstly, because I was fascinated by it in my youth. However, today, I want to develop modern 3D games, and my low-poly 3D Modelling/Animation skill level does not match up to the Photo-realistic Games I visualize in my mind’s eye.
- Develop games using low poly modeling styles
- Program tools that I can use to assemble more complex 3D models from smaller parts
- Learn to Model more complex 3D models.
- Acquire Equipment to Scan 3D Models Photogrammetry
- Purchase Photo-realistic 3D Model Assets from Marketplaces
- Recruit 3D Modelers/Animators with skills that match my vision to work for free or promise of royalty
- Hire 3D Modelers/Animators with skills to produce 3D Art/Animation to match my vision
Audio/Visual content is what is heavily consumed on the player side, thus in heavy demand. Subsystems can be reused in multiple Apps and products. So i would say learn Animation, 3D Modeling using Modularity, and Scripting in that Order.