No. Morals and ethics are a choice whether based on objective or subjective reality. Did you not see that I used the word “reason” in there. Of course if you reject reason then we have nothing more to say to one another.
Oh, excuse me. I was not aware this was still the eighteenth century. Where's my powdered wig?
The problem is, "reason" is 100% amoral. It can be used for any purpose, moral or immoral. A mass murderer can use "reason" every bit as well as you do, sir (or madam).
The only "natural laws" are those that say things like "if you jump off a cliff you will fall." There is no "natural law" promoting morality or ethics.
Morality?
1 Samuel 15:3.