Finding files to attach in Mail App

Hi

This is probably a very basic question but I cannot find a solution anywhere.

When creating an email in the mail app on my MBP, I wanted to attach a file that was saved in the pictures folder.

I cannot find any way at all to find this file to attach it - Once I click on the attach icon, my options on the left hand side are recents, applications, downloads, creative cloud. Then under iCloud heading - iCloud Drive, desktop, documents

The file is not in any of these locations

Does anyone know how I can add or look through additional folders to find the file I want to attach?

Thanks