I don’t think one needs a primer really - both face and eyes. As you become more familiar with how you like your makeup, you’ll understand if you actually need it. I think a sponge/beauty blender would be useful for foundation application.
You can use your fingers for eyeshadows if you go for easy looks. But overall 1 blending brush and 1 smaller (but still a bit fluffy) brush for more precise application would be the most useful.
If possible, you can try using your lipstick as a blush to see if you like it.
Less is more. And add products gradually one by one when you feel like you need it.
Foundation is absolutely unnecessary if you have clear skin imo. Spot concealing would be the way to go.