That wholly depends on what and how you’re animating. 2D animations with something like a CSS based animation software only require basically anything with a CPU. Simple 3D animations, like source engine, usually require either decent integrated graphics or a dedicated GPU. Complex 3D animations, like some of the stuff you can do with Blender, require at least 8ish GB of vram and a decent GPU. Then if you want to generate animations with AI, you’ll need at the bare minimum something like a 3090 (and a lack of ethics).

The VRAM is technically the only limiting factor in most cases, because you can only render what fits into it. The power of your GPU doesn’t really matter as to what you can render, just how fast you can render it. Within reason, of course. A thirty year old GPU isn’t going to be able to render things that rely on modern graphics APIs.

Most software also lets you render with a CPU, which just takes longer. So even a GPU isn’t strictly necessary. Just necessary if you don’t want to spend days rendering.