Problems with adding image or document in File Manager

When I add a file to File Manager, it has problems. That is, it does not allow me to upload images, text files or video.
They are presented as follows and cannot be used in any doctype.

when documents are uploaded, they cannot be downloaded or used within the system. When trying to download the following screen 404 is presented


Any help is greatly appreciated

Can you confirm the uploaded file is in directory: frappe-bench/sites/YOUR_SITE/public/files
Also if the directory has proper permissions for write for the nginx user?

Right click the broken image and see if its yourdomain.com/files/filename

thanks for answering.

I have confirmed that my .png file is located at the following path frappe-bench/sites/MY_SITE/public/files
I have just as the path shown above the broken image has the structure Free classifieds - yourdomain.com

Please, can you tell me how to check the permissions in nginx