You have all the powers that Putin currently does. Everyone feels the same way they do about you that they used to about Putin. You have his authority, for as long as you can hang on to it. You have none of his knowledge, however. The economic, military, social and political situations are the same as they now are. You are not inhabiting Putin’s body, you are just you. You’re magically transferred to the Kremlin.
How do you avoid falling out a window onto a pile of bullets your first week?
Realistically, nobody who has managed to reach Putin’s level is going to walk away. You’ve been plotting 24/7/365 since forever; quitting is not an option.
In the scenario you post the only thing one can do is to make a one time deposit of $100 million to a Swiss bank account, and then ask the security detail to escort one to the US embassy [the idea is that I am myself, just somehow in Putin’s office].
Once at the Embassy I claim to have no idea how I ended up in the Kremlin.