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?
I get on the first airplane to Europe and apply for political asylum when I get off.
Unless you already have strong connections and relationships with everyone else in the Kremlin you won’t last very long.