SharePoint 2013 has default approval workflow where we can enter the details of the users and the approval process starts through that all users.
I was looking same feature in Nintex office 365 too, but I was not able to find that in Nintex.
So How can I achieve that in Nintex. I am completely new to Nintex
Well, it's quite simple. Just create a workflow triggered when an item is created having the "assign a task" action or "start task process" depending on the number of approvers you expect (if only one, then "assign a task" is sufficient") and in the approve branch add action "set field in current item" to set file to be approved and for the reject branch to set file to be rejected.
When you configure your library to demand approval for the file when it is created, columns for its approval status will appear.
And that's it 
You can add additional "send email" actions to inform requester about the status.
Regards,
Tomasz
Hi Tomasz Poszytek, This was quite simple as you said. Worked :-)
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