The link to the Google Feedback tool is always available at the bottom of the page of a search result.
Click on the "Give us feedback" link to add a comment and capture a portion of the webpage that you are referring to.
Below link shows how to send feedback for Google's product:
Help improve Google’s products .
If you want to send the feedback to the Google photos team click on below link:
Welcome to the Photos Help Center.
Or you can join Google Photos Help Community to start a discussion. You will get expert comments here.
It really depends on the product which you want to report, so it can be read by the right people who're actually dealing with it.
For example on YouTube in footer menu you can click Help and Send feedback, which will open you feedback form and you can report anything including highlight areas of the page relevant to your feedback.
If you'd like to ...