The Ryze® Tello drone streams FPV video to the UDP port number 11111. This port is blocked by default in Windows Firewall.
To access the drone camera, unblock this UDP port in Windows Firewall:
Navigate to Control Panel > System and Security > Windows Firewall.
Select Advanced settings (on the left hand side tab).
Select Inbound Rules in the left pane.
Right click Inbound Rules and select New Rule.
Select the Port option and click Next.
Select UDP port and enter 11111 in Specific local ports and click Next.
Select Allow the connection in the next window and click Next.
Select all network types and click Next.
Name the rule and click Finish.