Controller uses Dto file to create a new user, does the Model it self needs to include restrictions?

public record RegisterRequestData(
  string UserName,
  string Password,
  string FirstName
  string LastName,
  enum Gender
);

public record RegisterRequestData(
  string UserName,
  string Password,
  string FirstName
  string LastName,
  enum Gender
);

public class PasswordHasher
{
  public string HashPassword(string rawPassword)
  {
    // the logic to hash password
  }

  public bool CheckPasswordHash(string rawPassword, string passwordHash)
  {
    // the logic to check if hash of rawPassword == passwordHash
  }
}

public class PasswordHasher
{
  public string HashPassword(string rawPassword)
  {
    // the logic to hash password
  }

  public bool CheckPasswordHash(string rawPassword, string passwordHash)
  {
    // the logic to check if hash of rawPassword == passwordHash
  }
}

public class UserData // this is database representation
{
  public string UserName { get; set; }
  public string PasswordHash { get; set; }
  public string FirstName  { get; set; }
  public string LastName { get; set; }
  public enum Gender { get; set; }
}

public class UserData // this is database representation
{
  public string UserName { get; set; }
  public string PasswordHash { get; set; }
  public string FirstName  { get; set; }
  public string LastName { get; set; }
  public enum Gender { get; set; }
}

public class UserModel
{
  public string UserName { get; init; }
  // public string Password { get; init; } <----- !!! there is no need for password here !!! you dont need this prop, you application doesnt care of user password
  public string FirstName  { get; init; }
  public string LastName { get; init; }
  public enum Gender { get; init; }

  public UserModel(string userName, string firstName, string lastName, enum gender)
  {
    // if checks for invariants, e.x. userName is not empty
    // assign values 
  }
}

public class UserModel
{
  public string UserName { get; init; }
  // public string Password { get; init; } <----- !!! there is no need for password here !!! you dont need this prop, you application doesnt care of user password
  public string FirstName  { get; init; }
  public string LastName { get; init; }
  public enum Gender { get; init; }

  public UserModel(string userName, string firstName, string lastName, enum gender)
  {
    // if checks for invariants, e.x. userName is not empty
    // assign values 
  }
}