What is the fate of a sworn oath by divorce not to sit in the workplace until the Maghrib prayer, then sitting in it, knowing that he had not consummated the marriage with his wife at the time of the oath, and that he informed her of a divorce occurring to her years after consummating the marriage with her and then took her back with her consent?

A wife with whom a legal marriage contract has been concluded is subject to divorce, even if consummation has not occurred. Your conditional divorce takes effect if you break your oath. If you swore an oath of divorce that you would not remain in the aforementioned place until the Maghrib prayer, and then you broke that oath, then according to the majority of scholars, the divorce has occurred. You could have explicitly told your father about your oath, and you are not obligated to obey him in matters that would result in the divorce of your wife.