Raise your camera to the height of your face. A couple of books under your laptop (and a straighter screen, by extension) can reduce the "looking up your nose" effect.
Consider a Bluetooth headset or even earbuds to make your voice clearer and block background noise for you and your listeners. If you have to make do with ordinary wired head/earphones, position the mic slightly beside your mouth so that it can stay as close as possible without you breathing into it.
Look at the camera, not the screen, when talking/presenting. It'll also help keep your mind focused, and not distracted by all the faces. If you need to look at the screen frequently for presentation notes, put the window you need as close to the camera as possible.
Always test your tech beforehand. You don't want to be the person who spends the first few minutes of the meeting making sure they're clearly visible/audible.