More simpler installing or API

Hello,
Maybe www-validator developers can do also a PHP-version of html
validation, that is downloadable and installable to localhost. Or make a
corresponding API. No well readable instruction could found.
For example this instruction https://github.com/validator/validator is a
very difficult (tirst steps not work) and i need such that instruction is
written so such that a beginner it-specialist/programmer can understand
well.
I'm searching possibility to validate many thousands of websites in a e.g
for-cycle.
Thank you