We have an requirement, where when the Read only file should not be allowed to copy.
How do we achieve this.
This is not the job of the storage system.
Think of it like me giving you money but telling you how to spend it. Once it's been transferred from my wallet to yours, I have lost control of it.
You're telling the storage system you want the users to be able to read the file but then have the storage system restrict what can be with the contents once the file has been been read. No storage system can control that.
You probably need to write or buy some wrapper code around the file access that enforces your policies. That's what Data Loss Prevention products are for.