Hi ashfields,
We'll be glad to help organize your folders in iCloud Mail. Let's follow the guidance to set up and sync your created folders across devices:
"iCloud includes seven default Mail folders: Inbox, VIP, Drafts, Sent, Archive, Trash, and Junk. You can create additional folders and subfolders to organize your email.
When you create additional folders, they’re visible on any device that has Mail turned on in iCloud settings.
To work with folders, make sure the Mailboxes list is visible.
Create a folder or subfolder
In Mail on iCloud.com, do one of the following:
- Create a new folder: While a default folder is selected, tap
next to Folders in the Mailboxes list. Type a name, then tap Return or Enter. - Create a subfolder: Select the folder where you want to add a subfolder, tap
, type the new subfolder’s name, then tap Return or Enter.
"
Organize email with folders in Mail on iCloud.com - Apple Support
Cheers.