How to tell PHP to use SameSite=None for cross-site cookies?

Question

According to the article here https://php.watch/articles/PHP-Samesite-cookies and PHP documenation at https://www.php.net/manual/en/session.security.ini.php, There are only

Answer 1

I am using cakephp 1.3. I need backend cookie at front-end that is not same domain. check in detail here.

https://stackoverflow.com/a/63481019/6128573