This guide will get you 98% of the way there; it's intended to show how to remove the circuit board that holds the electromechanical part of the buttons, but you would need to remove it to get to the physical push buttons themselves anyway.
[link|https://www.nadiemellamagallina.com/en/manuales/smartphones-1/google-580/google-pixel-7-1417/pulsadores-laterales-12909|Manuals / Google Pixel 7 / Side buttons - Nobody Calls Me Chicken]
The site is in Spanish, but use it with the Chrome browser and the translation will make the guide quite usable.