How do I find the place in front of someone?

In order to move the object in the direction the player is facing, you can use the lookVector property of CFrames.

One Local Script example would be:

local player = game.Players.LocalPlayer

game:GetService("UserInputService").InputBegan:Connect(function(inputObject, gameProcessedEvent)
	if inputObject.KeyCode == Enum.KeyCode.W then
		workspace.Cloud.BodyVelocity.Velocity = player.Character.HumanoidRootPart.CFrame.lookVector
	end
end)

If you want this event to occur on the server, you would need to use Remote Events

Note that the above function takes into account the direction the player was facing when key "w" was pressed and doesn't follow the player's change in direction.

In order to make sure the block was facing the player at all times until "w" was not pressed, you could use:

local player = game.Players.LocalPlayer
local prevent = false

game:GetService("UserInputService").InputBegan:Connect(function(inputObject, gameProcessedEvent)
	if inputObject.KeyCode == Enum.KeyCode.W then
		repeat
		workspace.Cloud.BodyVelocity.Velocity = (player.Character.HumanoidRootPart.CFrame.lookVector) * 1 -- Determines speed at which the block moves
		wait()
		until prevent == true
	end
end)

game:GetService("UserInputService").InputEnded:Connect(function(inputObject, gameProcessedEvent)
	if inputObject.KeyCode == Enum.KeyCode.W then
		prevent = true
		workspace.Cloud.BodyVelocity.Velocity = Vector3.new(0, 0, 0) -- Remove this line if you want the cloud to continue moving
		wait()
		prevent = false
	end
end)