So it is something like a facebook/instagram newfeeds feature! Right?
User can post an image with a title and a short description.
for this set of work you have create a logic where,
the image 1st get uploaded to Cloudnary DB and now after successful upload, run the 2nd logic which create a new bucket [ with a new id ] in you firebase db and store the details to specific tagg like Image, title & description.
Alo craete a shaperate tag [ say poast ] for home screen and store the new post bucket id in a list…
So that when the user opens the app it’ll load all the post according to the tag [ poast] list.
Hope this helps!