Answer:
This is TRUE.
Step-by-step explanation:
This are the first and second section of 25th Amendment which are stating that the vice-president will assume his position until the new president is elected. The same goes with the question of Vice president. New president is proposing who his vice president is, but Congress needs to confirm it.
For example when Nixon resigned, Gerald Ford vacated his position as a president. In the same time he choose Nelson Rockefeller as his Vice president.