Thank you for you answer ! As I wanted to use information from my post in my template, I couldn’t use a pattern with php, but they mentioned this documentation instead, so I used Block Binding with custom fields and it worked as excepted !
Thanks for your anwser !
I wanted to create a template file in php, because I want to add php code in this specific template. Is there a way to easily switch the “type” of my theme (from block based to classic themes) ? Or should I use a shortcode to add my php code to my template ?