You have all the powers that Putin currently does. Everyone completely loyal to Putin is now loyal to you. Enemies of Putin are enemies of you. Putin no longer exists, and there has been a clean and absolute transfer of power to you. 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. The world at large doesn’t know your past life, to them you have magically appeared as the new ruler. To everyone who knew you before, you just vanished.
Edit: no one knows your past life YET. They’ll quickly figure it out. You will not lose any support based on your actions in your past life.
Initiate special prosecution to investigate all of the former leader’s administrative state, changes made to law and the country’s oligarch class. Maybe based on Nuremburg trials structure, likely world experts on this type of investigation/prosecution brought in from outside of the country.
Negotiate immediate ceasefire with Ukraine, establish a council to fund and return Ukrainian children to Ukraine, restore land borders to pre-Russian invasion (at least), establish restitution to rebuild cities and support the people.
Demolish all levels of media censorship and open access to all information.
Tell China and North Korea that were no longer friends and publicly announce to donald that his last resort hidey hole is now closed, unless he wants the underground hitler suite complete with loaded gun, gas can and matches.
When all this is done, or far enough along to feel like it can complete, New democratic elections held for every seat of government, including my own. In strategic waves to preserve stability.