You only have to have half a brain to figure that out.
It takes less than half a brain, even yours, to know that the CIA has a multi-decade history of lying to the American public when it suits its perceived interests.
https://www.stonecoldtruth.com/the-cias-legacy-of-lies/
The CIA may or may not know the truth about Putin’s health and, if it does, it may or may not be lying about it. But everyone, especially those of us on FR, should take any CIA pronouncement on any issue with a high degree of skepticism.