Use an inner join in SQL Server

I am doing a practice with SQL Server and Go, and now I am making a query on a table which has an inner join against two tables, the main table is user and the tables to which it is performing the inner join are user state and user roles, but at the moment of being able to show a list of all the users, it shows me an object from the other two tables which I am doing the inner join.

This is my structure:

type User struct {
	Id_User       int64     `json:"id_user,omitempty"`
	Name          string    `json:"name,omitempty"`
	NameSecond    string    `json:"name_second,omitempty"`
	Surname       string    `json:"surname,omitempty"`
	SurnameSecond string    `json:"surname_second,omitempty"`
	Email         string    `json:"email,omitempty"`
	Password      string    `json:"password,omitempty"`
	Id_RoleUser   UserRole  `json:"id_roleUser,omitempty"`
	Id_UserState  UserState `json:"id_userState,omitempty"`
	CreatedAt     time.Time `json:"created_at,omitempty"`
	UpdatedAt     time.Time `json:"crated_at,omitempty"`
}

I know that it is showing me the UserRole and UserState structures as an object, because then I specify them but there is no way to be able to show only the name as if it were another field of the structure?

This my code:

func ListUser(w http.ResponseWriter, r *http.Request) {
	w.Header().Add("Content-Type", "application/json")

	var user model.User

	db := storage.Connection()
	tsql := `
	SELECT
		Id_User,
		U.Name + ' ' + NameSecond,
		Surname + ' ' + SurnameSecond,
		Email,
		UR.Name,
		US.Name
	FROM
		Users U
			INNER JOIN UserRoles UR ON UR.Id_RoleUser = U.Id_RoleUser
			INNER JOIN UserStates US ON US.Id_UserState = U.Id_UserState
	`

	rows, err := db.QueryContext(context.Background(), tsql)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	defer rows.Close()
	users := []model.User{}

	for rows.Next() {
		if err := rows.Scan(&user.Id_User, &user.Name, &user.Surname, &user.Email, &user.Id_RoleUser.Name, &user.Id_UserState.Name); err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}
		users = append(users, user)
	}

	if err := rows.Err(); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	json.NewEncoder(w).Encode(users)
}

This my JSON generated:

{
  "id_user": 5,
  "name": "Joan Sebastian",
  "surname": "Tovar Osorio",
  "email": "jsto@hotmail.com",
  "id_roleUser": {
    "name": "Desarrollador",
    "created_at": "0001-01-01T00:00:00Z"
  },
  "id_userState": {
    "name": "Inactivo",
    "created_at": "0001-01-01T00:00:00Z"
  },
  "created_at": "0001-01-01T00:00:00Z",
  "crated_at": "0001-01-01T00:00:00Z"
}

EDIT: You can implement the json.Marshaler interface and define the MarshalJson function for another struct which has your required fields.

type MyUser struct {
    Id_User       int64     `json:"id_user,omitempty"`
    Name          string    `json:"name,omitempty"`
    NameSecond    string    `json:"name_second,omitempty"`
    Surname       string    `json:"surname,omitempty"`
    SurnameSecond string    `json:"surname_second,omitempty"`
    Email         string    `json:"email,omitempty"`
    Password      string    `json:"password,omitempty"`
    RoleUserName  string  `json:"roleUser_name,omitempty"`
    UserStateName  string `json:"userState_name,omitempty"`
    CreatedAt     time.Time `json:"created_at,omitempty"`
    UpdatedAt     time.Time `json:"crated_at,omitempty"`
}

func (u *User) MarshalJSON() ([]byte, error) {
	mu := MyUser{
		Id_User:       u.Id_User,
		Name:          u.Name,
		NameSecond:    u.NameSecond,
		Surname:       u.Surname,
		SurnameSecond: u.SurnameSecond,
		Email:         u.Email,
		Password:      u.Password,
		RoleUserName:  u.Id_RoleUser.Name,
		UserStateName: u.Id_UserState.Name,
		CreatedAt:     u.CreatedAt,
		UpdatedAt:     u.UpdatedAt,
	}
	return json.Marshal(mu)
}