The first presidential use of a teleprompter occurred during the Nixon administration. President Richard Nixon used a teleprompter during his successful 1971 visit to China. The machine was brought in by White House Chief of Staff H.R. Haldeman and Presidential Counsel John Ehrlichman, who had seen it being used during political campaigns and thought it might help Nixon with some of his public speaking challenges (Nixon was known for going off-script and getting flustered when speaking in front of large crowds).
The device was placed on a table next to the podium, and Nixon's speechwriters fed him lines through an earpiece that he could then read aloud from the teleprompter's screen. The system worked well, and Nixon reportedly enjoyed using it; he even joked about it with Chinese Premier Zhou Enlai at a state dinner, saying "I'm sure you've all noticed that I have been equipped with an American invention which enabled me to say what I want to say without having to memorize my remarks."
Since then, presidents Jimmy Carter, Ronald Reagan, Bill Clinton, George W. Bush, Barack Obama, and Donald Trump have all used teleprompters during their time in office (although Trump has also been known to ditch the TelePrompTer mid-speech).