Installed windows 10 to mac and now ios doesnt work anymore

I bought windows 10 yesterday and installed it to my macbook pro. Now my computer cant find boot camp and it runs only windows. When I turn on the computer, it goes straight to windows-mode.... Basically i cant use ios anymore. So is it possible to uninstall windows in order to start running ios. Or is there any other ways.

Sorry about bad English 🙂