Continuing image display issues

I wrote the other day about my image(s) uploading but not displaying, and that my theme (Headway) doesn’t have the usual architecture of templates to meddle in.
I finally found a way to enter code in the equivalent of the single.php template.

1-But now I can’t for the life of me figure out what code to put there to enable the image upload(s) to display properly. I don’t know or understand php, but I can copy and paste. But there are so many different and (to me) meaningless codes floating around the forum and the readme and elsewhere, that I can’t figure out which to use.

2-I need to be able to display image captions. This could be challenging because the images are being uploaded apart from the media library. In other words they aren’t being sent in with a field to add a caption or an alt tag. So there’s only the file name which could often be meaningless.

3- I’m planning to allow people to upload up to 4 images (none is required). I need to figure out a way to display output that could vary quite a bit from post to post. I tried adding [gallery] and a couple of other image display shortcodes. They did allow the images to display, but with any of the gallery-like shortcodes it only worked with multiple image uploads. If there was only a single image, they won’t show that at all. So there needs to be a way to logically and attractively display a varying number of images.

I hope there are solutions to these issues. Thanks in advance.

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