Not sure if this will help, but this is how I have embedded my pics previously. This may not be what you want, and I'm sure there are other better ways to post pictures, but this has worked well for me.
I upload images to
Imgur, post them as "hidden", and use links from that post.
The code I use (thanks to @mitchell for help when I was learning):
[url=X][img]Y[/img][/url]
X = URL eg.
https://imgur.com/a/rkyTCwzY = Image address (right click and copy image address from post on host website) eg.
https://i.imgur.com/zybkwDB.jpgTo adjust size of pic add the letter "s", "m", or "l" after the last letter before ".jpg" in the image address eg.
https://i.imgur.com/zybkwDBs,m,l.jpg
This gives you small:
[url=https://imgur.com/a/rkyTCwz][img]https://i.imgur.com/zybkwDBs.jpg[/img][/url]
This gives you medium:
[url=https://imgur.com/a/rkyTCwz][img]https://i.imgur.com/zybkwDBm.jpg[/img][/url]
This gives you large:
[url=https://imgur.com/a/rkyTCwz][img]https://i.imgur.com/zybkwDBl.jpg[/img][/url]
Resulting in a size adjusted, linked (clickable for increased size), embedded picture.
You can repeat this code for each picture and center them, space them etc. with formatting based on each code input per separate picture
Hope this helps, or is useful for someone out there.
Geo