One song plays on the radio everyday. Recently, a new song played on the radio. A new song plays on the radio everyday.

Rowan, Thanks! I wanted to say there is one special song is played every day, of course they have other songs are played in the radio.

It depends on if you're trying to say that the radio only plays one song or that it seems to play one new song each day or that the same song gets played everyday. "Recently a new song plays on the radio everyday" means that each day a new song is played. "One song plays on the radio everyday" Means that one song is played everyday.