I would highly recommend learning more about webgl before diving into webGPU. https://webglfundamentals.org/ is a good place to start
[1] https://dmnsgn.me/blog/from-glsl-to-wgsl-the-future-of-shade...
Same applies to the 3D programming, while the way to implement something like deferred rendering (as an example) is different across APIs, it still is deferred rendering.