Event vs Delegate c#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication1
{
    class Person
    {
        public event Action PersonEat;
        public Action PersonEatAction;
        public Person()
        {

        }
        protected void OnPersonEat()
        {
            PersonEat.Invoke();
            PersonEat = null;
        }
    }
    class Program
    {
        private static void NotifyMe()
        {
            ///
        }
        static void Main(string[] args)
        {
            var person = new Person();

            // Only allowed inside type Person.
            //person.PersonEat(); // not allowed
            //person.PersonEat = NotifyMe; // fails


            person.PersonEat += NotifyMe;
            person.PersonEatAction();
        }
    }
}