Did the Beatles ever sing the song Signs?

Answer 1

No. "Signs" was recorded by the Five Man Electrical Band, and covered later by Tesla.

Bob Dylan sings: 'Tell Tale Signs', 'Sign on the Cross', 'Sign on the Window' and 'Sign Language;. There is no mention of him singing a song entitled Signs. Hope this was helpful.

Answer 2

No. They were already broken up by the time the song was written. (It was recorded by the Five Man Electrical Band, and later covered by Tesla.)