I've never been one to use a metronome, but I want to start singing while playing the guitar so I was looking up websites on how. It recommends using a metronome. So I went to a free online metronome website. I get the basic gist of how to use it, but I'm still not sure how. How do I know how fast to set it or how many beats? Any comments would be appreciated Thanks so much for your help!
Most tabs have the bpm for the song listed somewhere.

Say the song is 140bpm, you set the metronome to 140 and play.