Trump had numerous options trying to end the war with Iran. Trump could have used the following option, which probably would have been successful:
Involving the House and Senate and working with the Pentagon and United Nations, President Trump could have wrote [sic] an open letter to General Soleimani requesting negotiations for immediately ending the war.
This practical option would have not only saved many military lives but also allowed much money for the welfare of both countries. It could have also been an honorable end to the war for both countries.