The power the President has over “immigration” is limited to what is established by the Constitution. The President cannot establish new rules of Naturalization. He cannot issue waivers to overturn rules of Naturalization that are established in compliance with the Constitution.
From the issue of the ending DACA when this administration started by the Attorney General, building walls on the border of Mexico, the impending show of military might on a caravan fleeing persecution from a hostile country and now the ending of the constitutional birthright in the United States. It's kinda hard really to simply stay silent when all this adds to the divisions and the new way how people see America as a country.
The power over foreign immigration is delegated through Article 1 section 8 clause 4; “To establish an uniform Rule of Naturalization.” Because it is delegated under Article 1, we know this power is specifically vested in Congress. Separation of powers dictates that since the power to establish this Rule is rests in Congress, it cannot be exercised by any other branch. We can see that the executive branch cannot ESTABLISH the Rule of Naturalization, but what authority does the President have over the naturalization process?, quoted from Presidential Power Over Immigration article.
Hence, President Obama during his 8 years also wanted Immigration reform tried several times through Congress but was not successful. Finally, he came up with an Executive Order which created the DACA which the Trump administration tried to stop. Thanks to the courts, DACA recipients are still protected. It is an expected bombshell that right after hours when this so called new Executive Order to end the birthright of people born in the United States will immediately start the legal battle of lawsuits to challenge and stop this said order. Whether the US Congress will react on this Executive Order depends the outcome of the mid term US elections in two weeks.