How do I keep the camera only on me during a meeting

There are a few options based on what exactly you might need: 

• Setting in the desktop client (See myself as the active speaker while speaking) will show your self view any time you speak. 
• Pin video would allow to keep a specific user as the active speaker on your end of the meeting, but has no effect on others' view. 
• Spotlight video does the same as pin video, but affects all participants' view of the meeting. 

Hope that helps and please make sure to mark the solution as accepted if this information is what you needed.