Hi , @el5
Thanks for your quick response! We can use this code to get the delete file name on the Attachment control - OnRemoveFile.
Attachment - OnAddFile:
ClearCollect(attches , Self.Attachments);
Attachment - OnRemoveFile:
ClearCollect(removecol , Self.Attachments); ForAll(removecol , RemoveIf(attches As t1, t1.Value = Value && t1.Name = Name));
For example , if we upload three files:
1.png , 2.png , 3,png
And then we delete the 2.png , we can get the 2.png file name from attches collection.

Then we can pass this file Name to a new flow. Then we can use the flow to find the file in your sharepoint and then delete it in your flow. And you need to create a new flow to delete the file in my understand.
If this reply can help you , you can click mark this reply as solution (Accept solution) which can help more people, thanks in advance!
Best Regards,
Yueyun Zhang