upload image/files from fronted

Upload from the frontend and put them where? as a post?

What do you plan on doing with the images?

from my site users can already upload a post from frontend, but with no image.
i just want my users to be able to upload image from frontend, so that they choose their own Featured/thumbnail image on their post.

Not really sure on what you mean, but have you tried ‘Front End Editor plugin ?

Or Front End Upload maybe ?