Patreon clone - database

There is an issue I am finding, how do I get posts to have the field type ‘list of posts’

I can do list of texts, numbers etc but there seems to be no posts and I cant add my own as it’s a preselect-able list

I’m assuming ‘posts’ are a data type you created. In that case you would use the repeating group element to show a list of ‘posts’.