There and Back Again has exactly two lore counters on it.
Steps
At the beginning of your precombat main phase, There and Back Again triggers, putting a lore counter on it.
There and Back Again's third chapter ability triggers, creating a legendary 6/6 Smaug creature token and causing you to sacrifice There and Back Again.
At the beginning of your end step, Hazel of the Rootbloom triggers, creating a copy of the Smaug token.
Put either Smaug token into your graveyard due to the legend rule.
When the Smaug token dies, it triggers, creating fourteen Treasure tokens.
Activate Time Sieve by tapping it and sacrificing five Treasures, causing you to take an extra turn after this one.