Apple Watch series 3 info

Can you use the Apple Watch Series 3 without an iPhone or WiFi? Can you access it’s fitness features such as monitoring your heart rate and tracking your footsteps how many calories burned etc. with out having to have WiFi or your phone? For example if you go on a hike and want to track steps and don’t have phone/WiFi? Do you need it for just those specific features I know you’d be limited will those be available?