Short answers, pulled from the story.
Jefferson Davis was the only person ever to serve as president of the Confederate States of America. He took the oath of office on the 18th of February 1861 as head of the provisional government and served until the Confederacy's dissolution on the 5th of May 1865.
The Confederate president held the power of line-item veto, a tool that in the United States was mostly reserved for state governors. Jefferson Davis never exercised this power before the Confederacy's military collapse.
Davis was inaugurated as president of the permanent Confederate government on the 22nd of February 1862, at the statue of Washington on Capitol Square in Richmond.
In 1861, the Confederate president earned an annual salary of CS$25,000, along with an expense account and a nontaxable travel account.
Davis stopped exercising presidential powers after the Confederate States cabinet declared the Confederacy dissolved on the 5th of May 1865. Five days later, he was captured by elements of the United States Cavalry.
The White House of the Confederacy, also known as the Brockenbrough House, was a private residence purchased by the City of Richmond and leased to Jefferson Davis as an executive mansion. After the Civil War it held Confederate documents, relics, and pictures, and in 1896 it was redesignated the Confederate Museum.