I have the following questions about AMD:

1. If I want to switch to an AMD GPU, do I need to change my motherboard? Or do all motherboards work with both AMD and Nvidia GPUs?
2. Do I need to buy an AMD CPU as well? Or can I use my existing Intel CPU with an AMD GPU?
3. How does the AMD GPU naming convention work? More specifically, what is AMD’s equivalent of the RTX 4070? (I want to get a 4070 but I figured it would be a good idea to research AMD’s options)