Updating collections with unique user ID via memberships

Now that we have Memberships available, can we create a form where a user can submit some details and update the collection with a unique ID of the logged in user?

Basically, my use case is to allow users to do a journal entry and then show his/her entries on the profile or homepage.

Is this possible to do?

Here is my public share link: LINK
(how to access public share link)