http - How do I serve both web pages and API Routes by using same port address and different Handle pattern

Question

I have simple web application with CRUD operation, I want to serve web pages and API routes using same port address and different Handle pattern. As follows,

fs := http.FileServer(http.Dir("server/webapps/play_maths"))
http.Handle("/", fs) 

http.Handle("/api", call API routes)

Following is my API routes

func UserRoutes() *mux.Router  {
    var router = mux.NewRouter()
    router = mux.NewRouter().StrictSlash(true)
    router.HandleFunc("/user/create", api.CreateUser)
    router.HandleFunc("/user/get/all", api.GetAllUsers)
    return router
}

Answer 1

Waitting for answers