how do I get this stylized look in unity?

I kind of got it already, by changing the materials shader to Unlit but I want different parts of my Mesh to have different colors.
So how do I go about it?

Well, just color it? You probably don’t use any textures at the moment. Depending on the mesh topology you might be able to juse use vertex colors and a shader that does use the vertex colors of the mesh. If not you have to provide a texture with the colors you want and unwrap your model the way you need it.