The token copies exactly what is printed on the creature and nothing else (unless that creature is a token or is copying something else; see below). The token doesn't copy whether that creature is tapped or untapped, whether it has any counters on it, whether it has any Auras and/or Equipment attached to it, or any non-copy effects that changed its power, toughness, types, color, and so on.

If the target creature is itself a token, the token created by Littjara Mirrorlake's ability copies the original characteristics of that token as stated by the effect that created it.

If the target creature is copying something else, the token you create will use the copiable values of the target creature. In most cases, it will be a copy of whatever the target creature is copying. If it's copying a permanent or card with {X} in its mana cost, X is 0.

If the copied creature has {X} in its mana cost, X is 0.

Any enters-the-battlefield abilities of the copied creature will trigger when the token enters the battlefield. Any “As [this creature] enters the battlefield” or “[This creature] enters the battlefield with” abilities of the copied creature will also work.