how to change the picture of the top?

it’s located here
https://comobajardepesoya.com/wp-content/themes/amazing-grace/images/bg-portrait0.jpg

easiest thing to do would be create new image and name it same as old image
rename or delete old image
upload new image to same place

I assume you mean the image with the tape bearing the number 8? If so that image is located at wp-content/themes/amazing-grace/images/bg-portrait2.jpg or in this case comobajardepesoya.com/wp-content/themes/amazing-grace/images/bg-portrait2.jpg

You’ll need an image editor to get it to look right.

thanks man

Quick Draw McGraw beat me to it. ??

Looks like the theme is using a image rotator of some sort and can tell you where to change images and there might few images there in images folder
wp-content/themes/amazing-grace/images/bg-portrait3.jpg

so you can change those images keeping same size and same name.

they may be named bg-portrait 1 2 3