Recording problem

Windows 10 Audacity 2.1.2

I am unable to record music. My turntable is connected to my amplifier and the wire from the amplifier to my computer,carries the signal to the computer. I have checked the end of the wire and the signal is there. When connected to my computer and turned on it does not record the music

When the computer is all connected and turned on to record the music it actually records the sound in the room

See this set of tutorials in the Audacity Manual:

Basically the Device Toolbar needs setting so that the input device is your turntable (and you’ll want the output device to be the computer’s speakers).