According to the Apple Store website: as of June 7, 2023, the Apple Watch s8 is the latest model.
The s8 comes in 41mm and 45mm sizes. With all-weather retina display. both GPS and GPS+cellular versions. Support IP6X certification and 50 meters waterproof. Storage capacity are 32GB, built-in speaker and microphone, support LTE, wireless LAN, Bluetooth 5.0 and so on, both can receive calls, send and receive messages, listen to music and so on.