unityengine.vector3 does not contain a definition for length

i am making a multiplayer game where the player will be spawned in a random place after they died.
i follow instruction from youtube in this link

But when i tried to play the scirpt it give me an error that says unityengine.vector3 does not have an extension Length. is it depcrecated??

[ClientRpc]
void RpcRespawn()
{
	if (isLocalPlayer)
	{
		Vector3 spawnPoints = Vector3.zero ;
		// spawn back to zero location
		//transform.position = Vector3.zero;

		// If there is a spawn point array and the array is not empty, pick a spawn point at random
		if (spawnPoints != null && spawnPoints.Length > 0)
		{
			spawnpoints = spawnPoints[Random.Range(0, spawnPoints.Length)].transform.position;
		}
		// Set the player’s position to the chosen spawn point
		transform.position = spawnpoints;
	}
}

You have named your local variable in line 6 “spawnPoints”. You probably have a class variable that is also named spawnPoints. I guess you want to name the local variable “spawnPoint”.