i need help recording

every time i use audacity it only shows a flat line can some one help i have audacity 2.1.1 and my operating system is windows vista

We cannot see what you are doing so we can only help you in detail if you tell us exactly what you are trying to record and what equipment you are using to do that.

Generally in Audacity you must use Device Toolbar to select the recording device you want to record from.

Also see Why do I get only a flat line and no sound when I try to record?