Here are the quick steps to take when implementing a custom post type in GeneratePress.
1. Register your custom post type
You can either use the full method WordPress provided here:
https://developer.wordpress.org/plugins/post-types/registering-custom-post-types/
Or a use one of the tools like these:
https://generatewp.com/post-type/
https://en-ca.wordpress.org/plugins/custom-post-type-ui/
This sets the parameters of what the CPT can do, the slug for the templates to be used and where its displayed in the Dashboard Menu.
2. Acquire the templates
Take a copy of the single.php and the content-single.php, then rename them to they match the slug of your CPT tag like single-project.php and content-project.php.
3. Update the single-project.php file
In the single-project.php file, replace this line with the following:
get_template_part( 'content', 'project' );4. Edit the content-project.php file
Now you are ready to edit the content-project.php file if you need to adjust the structure at all.