How do I get a player's name when the player joins the game?

Use a PlayerAdded event!

Using the Players Service, we can tell when a player joins the game and get that specific player. Example,

-- Regular script
game.Players.PlayerAdded:connect(function(plr)
    print(plr.Name)-- Prints players' names
end)

Your question didn't say much about the follow brick thing, and you should try doing that yourself before posting another question.

How do I get the character?

This is what I think you meant. We can use the CharacterAdded event of the player we got from the PlayerAdded event. Example,

-- Regular script
game.Players.PlayerAdded:connect(function(plr)-- Gets the player
    plr.CharacterAdded:connect(function(char)-- Gets the character
        local Torso = char:WaitForChild("Torso")-- Gets the torso
    end)
end)

I also got the Torso defined for you so you can make that follow brick!

Good Luck!

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