how to host a webapi in world wide web

Question

I create a webapi2 in mvc5 project and I host the web API in IIS(internet information service) successfully and my web API works fine but the problem is web API is not accessed in anywhere means web API only access in the office location

 

I want to access web API anywhere but I don't how to deploy worldwide web means access everywhere

 

versions:

web API 2 framework

IIS Version - 10.0.17763.1

project version - MVC 5

 

help