A. Share control
Important: To use all feature, please install Microsoft Teams App instead of Teams on web.
To share control in a meeting, select Share content 
in meeting. Then, choose to share entire Desktop.
B. Give control
If user want another meeting participant or technical support to change a file, help to troubleshoot or demonstrate something, user can give control to that person. User and the participant or technical support will both be in control of the sharing, and user can take back control anytime.
Note: When you’re sharing an app, only give control to people you trust. People you give control to may send commands that could affect your system or other apps. We've taken steps to prevent this but haven't tested every possible system customization.
In our environment, a guest (no CNA login) is unable to get control.
On the sharing toolbar at the top of screen, user should select Give control.
Select the name of the person who the user want to give control to.
While user is sharing control the entire desktop, the technical support can make modifications in user's system.
To take control back, select Take back control.
C. Take control
On the chat, technical support must seek the user's approval for remote control before taking control. The record of chat should be kept. To take control while another person is sharing, select Request control. Then the person sharing will approve or deny your request.
While a technical support has control, the technical support can make modifications in user's system,
When the technical support finish troubleshooting or modification, select Release control to stop sharing control.
Remarks: If a mouse pointer is out of Teams screen, the toolbar would be hide automatical