please i need brief on the below video conference features
Concurrent Callers ( for example : 50 Concurrent Callers )
Dual Screen for Video and content
Two Simultenous content sources and Supoort Dual Presentation
Tele Lense Field of View
Enabling Analytics for better resources planning
Most of the newer devices will meet your requirements. I'd suggest that if you want a proper design that you get in touch with one of your local Cisco Partners who should be able to help you.
The Cisco Partner Locator tool can be found at https://locatr.cloudapps.cisco.com/WWChannels/LOCATR/openBasicSearch.do