how can you not have these fields? there are exactly the same fields and settings as on the demo variant. if I don't put an image in the Author tab, the photo field, no photo appears for the author. Neither in my website nor in the demo. I used exactly the same settings. you can check them in the back.
does not work properly with your template. I followed exactly the same settings. the proof is below.
if you were right, the question arises: where should I upload the image of the author? in your demo it is as shown in the images below.
in image 1 it is as it appears in the demo
In image 2 is the identical setting on my website