Reports

[Adriel]

How we can view a user browsing history in the 1800?

[PhoneBoy]

To tie in usernames, you'd have to integrate the gateway with your Active Directory server (i.e. Identity Awareness).
To get the history, you'd have to ensure App Control and URL Filtering are enabled and that you're logging.
You can see what a user did for the last hour/day via Logs and Monitoring > Status > Monitoring.
For anything more detailed than that, you'll probably need to use SMP or SmartEvent.