In his annual state-of-the-nation speech on Wednesday, President Vladimir V. Putin of Russia shook up the country and its political class by calling for constitutional changes that would give him a new path to holding onto power after his current — and, in theory, last — term ends in 2024.

With that, the entire cabinet, led by a long-serving Putin ally, Prime Minister Dmitri A. Medvedev, abruptly resigned. The head of the Federal Tax Service, Mikhail V. Mishustin — a little-known but skilled technocrat — will become the next prime minister.

The spate of moves offers some clues about Mr. Putin’s plans and priorities, but also raises questions about what may lie ahead for the Russian president. Here are answers to some of them.

What is Putin doing?

Mr. Putin’s hold on power in Russia is unrivaled, built up over the last 20 years in his posts as president and prime minister.