dynamic php inside wordpress page

What you can do is to use a shortcode, for example, you can add them to your functions.php or create a plugin that does the same.

Check this guide, but keep in mind there is a lot of information about WordPress and shortcodes.

In the end, you will only have to call your shortcode wherever you want. Shortcodes can use attributes so you could end with something like this:

[memberThing description="yes"] //...

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