In These new engines it takes about 30s for the oil to reach the head of the engine so it can start lubricating the valves. But it's always best to let the engine warm up before moving.
That's false on modern cars, for a few reasons.
1. The engine takes longer to get to operating temperature when idle.
2. Engines are machined to greater tolerances which allows them to hold a good seal even when cold.
3. Engines now have anti-drainback valves so the heads don't initially starve of oil.
Warming up an engine before moving was needed in the 60s; it hasn't been needed for the last 30 years now.