Считать файл XML - C#

<univer>
    <faculty name = "Mex-mat">
        <group name = "421">
            <student name = "Ivan">
                <sername>
                    Ivanov
                </sername>
            </student>
        </group>
        
        <group name = "422">
        </group>
    </faculty>
</univer>
 
 </faculty>

using System;
using System.Collections.Generic;
using System.Xml;
namespace Dekanat
{
    class Student
    {
        private string name;
        private string surname;
        private int zachetka;
 
        public Student() { }
 
        public Student(string surname, string name, int zachetka)
        {
            this.surname = surname;
            this.name = name;
            this.zachetka = zachetka;
        }
 
        public string Name
        {
            get { return name; }
            set { name = value; }
        }
 
        public string Surname
        {
            get { return surname; }
            set { surname = value; }
        }
 
        public int Zachetka
        {
            get { return zachetka; }
            set { zachetka = value; }
        }
 
        public void ShowStd()
        {
            Console.WriteLine("Фамилия: {0} \nИмя: {1} \nНомер зачетки: {2}\n", surname, name, zachetka);
        }
    }
 
    class Group : Student
    {
        private int number;
        protected List<Student> student = new List<Student>();
 
        public Group() { }
 
        public Group(int number) { this.number = number; }
 
        public void addStudent(params Student[] stud)
        {
            for (int i = 0; i < stud.Length; i++)
            {
                student.Add(stud[i]);
            }
        }
 
        public void removeStudent(Student stud)
        {
            student.Remove(stud);
        }
 
        public void ShowGrp()
        {
            Console.WriteLine("Номер группы: {0}", number);
 
            foreach (var item in student)
            {
                item.ShowStd();
            }
        }
    }
 
    class Faculty : Group
    {
        private string faculty;
        protected List<Group> group = new List<Group>();
 
        public Faculty() { }
 
        public Faculty(string faculty)
        {
            this.faculty = faculty;
        }
 
        public string _Faculty
        {
            get { return faculty; }
            set { faculty = value; }
        }
 
        public void addGroup(params Group[] grp)
        {
            for (int i = 0; i < grp.Length; i++)
            {
                group.Add(grp[i]);
            }
        }
 
        public void removeGroup(Group grp)
        {
            group.Remove(grp);
        }
 
        public void Show()
        {
            Console.WriteLine("Название факультета: {0}\n", faculty);
 
            foreach (var item in group)
            {
                item.ShowGrp();
            }
        }
    }