I did not advocate any such action, I am curious however...where is the President empowered by the Constitution to write or repeal laws, or overturn Supreme Court opinions?
Nowhere, which is why we still have abortion.
The biggest thing the president can do is speak out forcefully about the horrors of abortion, and make it clear it is wrong.
The biggest thing pro-life supporters can do regarding the presidency is not to cast votes which allow pro-abortionists to claim that we like power more than our principles, and that we'd sell out those babies we say are alive just to keep hold of the presidency.