I have just had a quick play on Banned Story with how to do things properly. I did explain most things on my Padlet. Basically, I realised that all side scrollers are made of 3 things. Backgrounds, Midgrounds and Foregrounds.
Backgrounds – Usually blurred out with small to none outline at all, not too detailed.
Midgrounds – Usually clear to make out what it is, No to faint outlines. Detailed
Foreground – Has sharp outlines, very detailed.
I have found all of these sprites and objects using the Banned Story software which is like a giant database for the game that I play called Maple Story.