How can I block the afternoon sun from coming through kitchen window?

Jane: I put in a rolling outdoor shade. It really helps!

https://www.homedepot.com/b/Window-Treatments-Shades-Outdoor-Shades/Light-Filtering/N-5yc1vZbt0zZ1z0yk9w

Hi Jane, here is a link for a no sew shade you can make

https://www.younghouselove.com/diy-window-shade/

Here is a video for a DIY roller blind as well

https://www.youtube.com/watch?v=s92uekTMAJE

I have pleated shades that roll all the way, they practically disappear when open, but they are easily lowered when needed. Or your could add a sheer curtain panel on a rod with ring and draw it across the window during sunny hours. The light will still come through, but the blinding sun will be diffused. You could do the same with a heavier material if you don't want any light.

An outdoor awning, either fixed or retractable is another option.