cannot record please help

We just bought a Logitech mic and are trying to record for a school project. I can hear myself in the headphones but there is no audio wave and nothign plays back. What are we doing wrong?

You need to select the microphone as the recording input.
I can’t be more specific as I’ve no idea what sort of computer, what operating system, or which version of Audacity you have.
You may find something here that will help:

Can Audacity record streaming media from the web? I’m wondering if someone designed a plug-in that can do this? I want to record a gathering for my link removed site but I can’t figure out a way to record the streaming audio.
They don’t all work. Newer computers make it harder and harder. Macs have never been able to do this without adding software.