How can I access a PHP page from a specified page link?

How can I access a PHP page from a specified page link? How can I access a PHP page from a specified page link? Page B must be accessed through page A. you are redirected from page A to page B. If you need required parameters in php, value, you can enter this value ($ _ POST []): how can a PHP page be accessed from a specified page link?
How can I access a PHP page from a specified page link?

Page B must go to page

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You are jumping from page A to page B. If you need A required parameter in php, you can determine the value ($ _ POST, if yes, perform location jump or 404.
If there are no required parameters, you can manually give them a parameter.
It is troublesome to use session.

$ _ SERVER ['http _ referer']
Directs the user to the address of the previous page of the current page (if any ). Determined by the user agent settings. Not all user proxies set this item, and some also provide the HTTP_REFERER modification function. In short, this value is not credible.