help with declaration of LINQ to EF query

public class PhysicianInfo2
    {
        public PhysicianInfo2()
        {
            foreach (System.Reflection.PropertyInfo info in this.GetType().GetProperties())
            {
                if (info.PropertyType == typeof(List<string>))
                {
                    info.SetValue(this, new List<string>(), null);
                    continue;
                }
                info.SetValue(this, string.Empty, null);
            }
        }
 
        public string NPI { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string MiddleName { get; set; }
        public string Prefix { get; set; }
        public string Suffix { get; set; }
        public string Email { get; set; }
 
        //------- can be a list
        public string Speciality { get; set; }  //(this could be a list)
        public string Institution { get; set; } //(this could be a list)
        public string Status { get; set; }      //(online, offline, busy)
}

var item2 = (from item in _context.Physician.Include("PersonalInfo")
 
                             let specialities = (from spec in _context.PhysicianSpecialty.Include("Speciality")
                                                 where spec.PhysicianID == item.PhysicianID
                                                 select spec.Specialty)
 
                             select new Models.PhysicianInfo2()
                             {
                                 NPI = item.NPI,
                                 Email = item.PersonalInfo.Email,
                                 FirstName = item.PersonalInfo.FirstName,
                                 LastName = item.PersonalInfo.LastName,
                                 MiddleName = item.PersonalInfo.MiddleName,
                                 Prefix = item.PersonalInfo.Prefix,
                                 Suffix = item.PersonalInfo.Suffix,
                                 Speciality = (from subItem in specialities
                                               select subItem.Name).Aggregate((a, b) => string.Format("{0}, {1}", a, b)),
                                 Institution = string.Empty
                             });
 
                count = item2.AsEnumerable().Count();