How to return a list in ASP.NET Core

I have created an ASP.NET Core project in web API, in my controller I am trying to list my users but it gives me an error, the list of users is in my controller I have only added two users, what am I failing in? is it ok to create my user list in my controller?

this is my controller

using Microsoft.AspNetCore.Mvc;
using Project001.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

// For more information on enabling Web API for empty projects, visit https://go.microsoft.com/fwlink/?LinkID=397860

namespace Project001.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class UserController : ControllerBase
    {
        // GET: api/<UserController>
        [HttpGet("lista")]
        public ActionResult listaUsuarios(int id)
        {
            var usuarios = from user in users()
                           where user.id.Equals(id)
                           select user;
            return (ActionResult)usuarios;
        }

        [NonAction]
        public List<User> users()
        {
            return new List<User>
            {
                new User
                {
                    id=1,
                    nombre="juan",
                    apellido="torres",
                    numero=12345
                },
                new User
                {
                    id=2,
                    nombre="pepe",
                    apellido="luna",
                    numero=678910
                }
            };
        }
    }
}

this is the error i get