Hi @stew
I’m afraid you need to create a custom widget to do that. Please take a look at these pages: http://www.wpbeginner.com/wp-tutorials/how-to-create-a-custom-wordpress-widget/, https://codex.wordpress.org/Widgets_API.
If you don’t know anything about programming and don’t have time to learn it, I suggest you hire a developer to help you out with it, and I’d recommend looking for one on https://studio.envato.com/ or https://www.upwork.com/.
After you created the plugin, you can use the solution on the following page to filter the post: http://www.advancedcustomfields.com/resources/creating-wp-archive-custom-field-filter/.
Hope this helps!
