Hi there,
Are you trying to embed the form on ALL posts? Do you have the code for the form?
If so, you can use the Hook Element to insert your form after the post content.
https://docs.generatepress.com/article/hooks-element-overview/
Here’s how:
1.) Make sure the Elements module is activated in Appearance > GeneratePress
2.) Once activated, go to Appearance > Elements
3.) Click Add New Element button on the upper left corner, a dropdown should pop up. Pick “Hook”.
4.) Once you’re on the Hook Element UI, paste your form’s code on the code area. If it’s a PHP code, make sure you check “Execute PHP”. If it’s a shortcode, check “Execute Shortcode”
5.) Set the hook dropdown to generate_after_content
6.) Go to the Display rule tab.
7.) Set the Location dropdown to “Post – all posts”
8.) Save or update it.
If you’ve successfully followed these steps, you should see the form on the bottom of the posts.