Where to locate php.ini?

Hello,

I am fairly new to Docker.

I established a local server stack on my computer using docker-compose.
I created a script and it installed wordpress, mariadb, and phpmyadmin.

But when I try to upload a theme to my wordpress site, it says “the link you are following has expired”. And I think it has to do with the file upload limits. (correct me if I’m wrong) and can be solved by increasing the maximum file upload size limit in php.ini file ?

I don’t know where to find the file.

Please help.