Where can I find the hidden jpg files on my mobile phone?

So, I messed around with my pc and mobile phone because I wanted to import the pictures from my smartphone to my computer. To my admiration, my laptop found so much junk on my phone. I've searched everything possible on my smartphone, but can't find these files.

These could be application assets. Wouldn't delete anything just like that.
In response to the question: Of course, you have to use a file explorer on your smartphone that can display hidden files.

Looks like candrush or one of those similar games

May be. But the thing is, the pictures I saw there are from some kind of game that I never had on my phone

Some games may already be preinstalled or permanently integrated into the OS, some manufacturers do so, e.g. Samsung. There's e.g. Facebook is also part of the OS or a system app that can't be removed.