I need do get a specific element in my array to make a validation and get a return of a specific navigation bar. navigation.ts

public get() {  
    this.uuid = this.usuarioService.usuarioConectado()
    let ref = this.usuarioService.getUsuario();
    ref.once('value', (snapshotChanges) =>{
      this.usuario.push(snapshotChanges.val())
      console.log("this.user.push", this.usuario)
      let usuario_logado = this.usuario[0][this.uuid]
      var role = this.usuario[0][this.uuid].role
      console.log("USER LOGADO", usuario_logado)
      console.log("ROLE USER LOGADO", role)
      this.role = role
    }).finally(() => {
      switch(this.role){
        case "USUARIO":{
          console.log("USUARIO||ON")
          return NavigationItems
        }
        case "OPERADOR":{
          console.log("OPERADOR||ON")
          return NavigationItemsParceiros
        }
        default:{
          console.log("Role não definida")
          return NavigationItemsParceiros
        }
      }
    })
  }
}

But, in this way, i don't get the return of NavigationItems/NavigationItemsParceiros, only read the console.log, how is the correct way to do that