re: "Just tried to upload three photos, all went to the text field. When I click on "Upload a File", I do not see any options or further instructions, just that file of photos."
Just so I understand, you drag three photos into the text field. That's the end of the upload process, at least for Mac and Windows. (Don't know about your OS...) There's no other step until you assign which size you wish to view the pic, thumb or full. There's not even a button to say "Go". It starts happening when you drop the file in the text box.
Another, completely separate, way to upload things is by clicking on "Upload a File". Clicking that button is redundant and unnecessary in the process of dragging pic to the text box outlined in the paragraph above. Rather, it is a way to do it if you don't do drag-and-drop. If you do both, it probably cancels drag-and-drop and restarts the process as "pick a file" from the directory shown.
If you use "Upload a File", then next step is to choose which one to upload -- hence being shown the folder of photos. In Windows and Mac, you'll click on a file to choose it, then select something that says "do it", either choose/open/execute, whatever. Then the upload process starts, and you'll likely see a progress bar.
You'll have to work out how to switch directories you're being offered to select from, or how to get your pics into that directory. I'm not the guy for Linux-related stuff, but if it's a graphical user interface, it's probably straightforward, with drop-down menus, etc. Undoubtably there's a YouTube video or two about it.
the beautiful thing about age is that picture looks new every time...
