Yes, it's described in the "dynamic forms" section of the help page.

What this allows you to do, is dynamically (in real-time) build a form and use any form configuration (the ones you already setup) to determine admin email, whether or not the visitor gets a confirmation email etc.

Sorry I missed the 'post' part. Executing PHP within a page is easy, since you can create individual page templates and add code wherever you want to. In posts, this can be a bit more tricky:

Either try the Inline PHP plugin that support PHP function calls from within a post, or modify your index.php / single.php theme templates to meet your requirements (eg. include the form at the end of a post).

Note: However, if you have multiple posts on a page and each owns a form, you need to make sure that every dynamically created form has a unique, corresponding form definition (in cforms admin pages). Multiple dynamic forms on the same page are not allowed to reference the same form 'template' created in the admin UI. Hope this makes sense.

My recommendation: If dynamic forms in posts are required, have the form only show up in the single view (visitor must click on the post). Then you only need to edit single.php to do what you want it to and you can get away with using just one form definition (since you'll only be showing one form at a time).

A bit cryptic, but I hope this makes sense.