I want to create a folder on my iPhone

Hello VetUS1usmc, To create a new folder in iPhone Mail just Open Mail, click on Mailboxes in upper left corner, click New Mailbox in lower right corner, Type the name of the new Mailbox Folder, then under Mailbox Location click and If you want it under the MAINl Mailbox like iCloud just press iCloud and the new mailbox folder will be created. If you want to make a SubFolder under a current one you already have just press the name of the folder and the new one will be created under the folder you select. Hope that makes sense. Let me know if you need further clarification.

If you were able to create the new folder, you have an IMAP account.

I just want to add that you must have an IMAP email account. If by some chance you still have a POP account, you cannot create mailboxes/folders.

Go to app folders and hold an area where there is nothing then you see a option create new folder