A pardon can only be given after a conviction. And he cannot wave a magic wand and make them all Citizens.
Not so. Gerald Ford, after assuming the presidency upon Richard Nixon's resignation, pardoned Nixon, and Nixon had not been convicted of any crime.
That act by Ford probably cost him re-election in 1976, putting the odious Jimmy Carter in the oval office.
Still, it was the right thing to do. It saved the nation the disaster that the indictment and trial of Nixon would have been.
He can not legally order that illegal aliens not be deported, but he has already signed an EO doing just that and no one is stopping him even today.
Actually, Gerald Ford issued a pardon to Nixon
before he was indicted in the Watergate mess.
If only LL’s emails surface will we ever know if Obama is the criminal mastermind that many of us suspect...