Thank you for your post.
FileMaker Pro does not have a File List field like Bento, but you do have the ability to add a file to a Container field, and you can either store it internally or as a reference; the latter similar to Bento. You can also make the Container field a repeating field allowing you to reference more than one file per record. This is how it is done.
1. Pull down the File menu and select "Manage -> Database..."
2. Click the Fields tab (if not already active).
3. Create a new field named "Files" with the field type set to "Container".
4. Click OK and return to Browse Mode.
5. Put your cursor in "Files", pull down the Insert menu and select "File..."
6. Find the file you want to attach. At the bottom of the dialog box, be sure to check the option, "Store only a reference to the file".
7. Once the file is attached/inserted, you can double-click the file, and the file will open in its native application.
If you want to store multiple files per record, return to "Manage -> Database...", select "Files" and click "Options...". Next, click on the Storage tab, and under "Repeating", change the Maximum number of repetitions to 5 (or a number that is comfortable for you).
Exit out of Manage Database, pull down the View menu and select "Layout Mode". Double-click the "Files" field, and at the bottom of the dialog box, you want to show repetitions 1 through 5, and the orientation is vertical (although you could also use horizontal). Click OK, and you will see five references of the field "Files" running down the page.
This should get you pointed in the right direction. Let me know if you need clarification for any of the above steps.