This text is part of the OBS UI - not part of the scene you are streaming (unless you choose to include OBS itself in your stream, which is usually not useful). So no one but the OBS operator will see that text.
It appears that your Window Capture source is linked to a monitor rather than to a particular program. So if you switch between windows on that monitor, people watching your stream SHOULD see the contents of whatever window(s) you have on that monitor.