When a user deletes their OneDrive account, any files that were stored in their OneDrive will also be deleted. If the user has any shared folders, those will be deleted as well.
How Do I Delete Files From OneDrive
Frequently Asked Questions with answer of What happens when OneDrive account is deleted?
All of the files that are stored in that OneDrive account will be deleted and will no longer be accessible.
No, deleting OneDrive will not delete your files.
There is no way to recover a deleted OneDrive account.
If an account is deleted, any files that were shared from that account will no longer be accessible.
Microsoft does not delete inactive accounts.
The answer to whether or not you need OneDrive depends on how you use your computer and how much storage space you need. OneDrive is a cloud storage service that comes with Microsoft Office 365. If you use Office 365, then you may find that OneDrive is a convenient way to store and share files. However, if you don’t use Office 365, then you may not need OneDrive.
It is up to the individual to decide if they want to delete Microsoft OneDrive or not.
Deleting from OneDrive does not delete from phone.
Conclusion
Once an OneDrive account is deleted, all files and data associated with that account are also deleted. There is no way to retrieve deleted OneDrive accounts or data.