How To Test Webcam For Zoom Conference?

[shivvy]

I am doing a Zoom conference later today and want to check that my laptop webcam is working. However I can't get it to open.
My laptop is a HP and I have Windows 7 Professional.
I can see 'HP HD Webcam' under Imaging Devices in Device Manager but I don't know how to open it. I can't find it when I do a search.
Help needed in the next hour if possible please!
Thanks.

[shivvy]

I also meant to say that I have looked up HP help and it says to search for and open 'YouCam'. When I do that, an image flashes up for a second and then disappears and nothing opens.