Quick Scoop: If you mean the Roblox Advent Calendar from 2021, the basic idea was to open the day’s door each day and claim the reward inside. Roblox’s help page also explains the general way to play Roblox: install Roblox Player, go to a game page in a modern browser, and click Play.

How it worked

For a Roblox Advent Calendar-style event, players usually:

  1. Open the Roblox experience or event page.
  2. Find the calendar area.
  3. Click the current day’s door or reward.
  4. Return the next day for the next item.

That matches the common 2021 Roblox Advent Calendar content seen in videos and guides from that period.

Playing Roblox itself

To play normal Roblox games, the official steps are:

  • Install Roblox Player.
  • Open Roblox in a modern browser.
  • Log in and choose a game.
  • Click the green Play button.
  • If prompted, allow Roblox to open and install.

2021 context

In late 2021, Roblox Advent Calendar content was showing up across toy unboxings and holiday guides, so people often used “calendar” to mean a seasonal Roblox event rather than a built-in app feature.

Clean version

If your question was simply “how do I play Roblox in 2021?”, the answer is: install the player, open a game, and press Play.

If you meant a specific Roblox Advent Calendar game or holiday event, I can help identify the exact one from the title.