Thanks @swathi.vadlamani for your response. Actually you are using Gmail as a mail service provided, which provide list of Emails in that view by default, in which you see emails as thread. So this thread view is a feature of Gmail.
But for other mail providers or applications like Outlook, it doesn’t show the emails like thread by default. Due to which user can’t see the earlier mails in the same context. To understand the email context we need to open that email itself and from the body itself we generally see the previous emails chain.
And as a standard feature of any email, whenever we reply to an email, it also contains the previous email body as a reference chain automatically. So which I asked should follow the same standard behavior irrespective relying on UI how it is rendering the list of emails.
I hope you understand which I am trying to convey here, in-case of any details please let me know.