If its a cardioid pattern mic (it probably is), they are less sensitive from the back -- so if you can have the back of the mic point at the keyboard, that would help.

If you don't mind that I self post to a youtube video, but this segment shows how the pattern and placement of the mic can reduce pc fan and keyboard noise.

https://youtu.be/7WyNIQlOFIA?t=858

First of all, there's nothing special about USB mics in terms of picking up ambient noise. Two main types of mics are dynamic and condensers, and there are models with USB-connectivity of both those types.

Secondly, hearing typing when someone types is ok, so please don't treat it as a problem in itself. Obnoxious noise level is a problem, which can be solved by increasing SNR: bringing the mic closer to the sound source, swapping a mic for another transducer type or another polar pattern, putting some kind of dampening on the line of sight between the mic and the noise source.

I've written a guide for voice recording which covers most of the basics. Hope you'll find it helpful: https://indiscipline.github.io/post/voice-sound-reference/

I have enough space on my desk to be able to fit a second wireless keyboard when I need to type and talk at the same time during meetings. This keyboard is much quieter than my mechanical keyboard.

One thing I need to get around to doing is to configure somewhat to let me mute with a keyboard shortcut when Zoom/Teams/etc. is not the active window. Why there isn't a built-in universal shortcut is very confusing to me.

As others have mentioned, keeping the mic closer to you and turning down the gain helps.

You can also run the mic through a signal chain and use a noise gate. So audio only gets sent when it reaches a certain threshold. On linux you can do this with pulseeffects if you're using pulseaudio.

The other hack is just mute yourself. I use a shortcut to do that when I'm typing and not actually talking.

Some virtual camera software comes with audio noise reduction. I use SplitCam on Windows. It doesn't eliminate keyboard noise entirely, but it does help. And it has the advantage of working on Teams, Zoom, etc, so that I have one place to set it.

A software solution like Krisp is an easy solution that goes a very long way.

I type on a different computer. I use a desktop system for video conferencing (which has a mechanical keyboard) and do any typing, e.g. for note taking, on a separate laptop.

Get the mic close to your mouth and turn down the gain. This will also increase the quality

Headworn dynamic mic.