how can i make google sheet itrate over columns

Question

I have a sheet like this how can make a cell in front of x under the sum column get the sum of the x count column and y get the sum y count column of course, I use sum function on both but the issue I face is how to make the z ,x1,y1,z1 the same I try to fill it down but as you see in the picture it is wrong how can I do it for 100 row ?

Answer 1

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