It’s common, universal knowledge that the iPhone 7 comes without a headphone jack. The only way to listen to music on it is to buy the overpriced wireless EarPods that Apple is selling, or through a lightening-cable headphone. But then you cannot charge your phone and listen to music at the same time.
Youtuber TechRax made a “hack” video in which he drilled a hole into an iPhone 7 to reveal the secret headphone jack which lets you use your 3.5mm headset to listen to music.