How can I know the changes of the the update, because it only tells me: an improvement in the security, but it's not just that, I saw thing at the camera that didn't exist, and other things
You will need to turn on your internet access.
On your phone, please access "Settings," select "About phone," then select "Android security patch level."
When you select "Android security patch level," it will access the Android Security Bulletins website.
Please select "Samsung" in the devices list, which will access Android Security updates for Samsung. Security updates are listed by the month that they were released at the top of the website. By clicking on the month the security update was released, you may find out what was updated.