Images not loading on webpage, and links to other media give 404 Not Found

Had some recent problems where to start with only homepage text was visible, all other pages/links gave 404 Not Found.

Now managed to get pages to function but all images fail to load, plus links to other media give “Sorry, this page doesn’t exist. Please check the URL or go back a page. 404 Error. Page Not Found”

Media files are all there in wp-content/uploads so something is preventing site ‘seeing’ them, suspect the same issue is causing the problem with the images and the media files.

Also RSS feed not working but as this too depends on a link maybe is part of the same problem?

Have deactivated plugins in case there was a conflict but this does not help.

NB I’m an admin not developer, ie a real novice, can get into files via cPanel, can edit text in files given instruction but not much more…..