Need some help trying to create a list page with a description and image

Hello!

I have a parent page which has 4 child pages. I would like to show the child page title, grab a few lines of text and also show a image on the parent page.

The title and short description will exist on the child page but the image/thumbnail will need to be made just for the list page, I’m guessing unless there’s away of taking the image from the child page and turning it into a thumbnail?

I’ve been scolling through google for 2 days trying to find something without success.

This isn’t a widget it will live in the main page content and it will not be on every parent page.

Can anyone please help me and guide me through the code bit if there are code changes need.

Many thanks
Sarah