Apple has a Lightning adapter for the iPhone 15, but you shouldn't buy it
Lightning to 3.5 mm Headphone Jack Adapter for iPhone Lightning Jack Adapter Connector to 3.5mm AUX Audio (for iPhone 7/8/X/or Latest Version) - Walmart.com
Lightning to 3.5 mm Headphone Jack Adapter - iPhone 3.5mm Headphones/Earphones Jack Aux Audio Dongle Adapter Compatible for iPhone/iPad SP-IPHONE-HEADPHONE-ADAPTER
Aluratek Dual Lightning Adapter for iPhone/iPad ADL01F B&H Photo