Based on the game by Black Lilith.
Do other animals have consciousness and/or free will?
Keep in mind there are graded levels of consciousness.
At the very lowest levels, creatures are merely S-R reactive, such as a worm turning away from heat.
It is conscious but only possesses a very low level of it. At higher and higher levels of creature, the level of consciousness increases in terms of abilities.
At a high enough level, the brain can support the precursors of language.
As things ascend from there, the ability to handle language complexities increases.
I note that a baby cannot speak, yet is conscious and human. But matters are more complicated than this simple model: the subconscious processes also can handle some elements of language.
For example, at high enough brain architecture levels, the visual processing system can learn features and although it may not have a conscious word for a feature, it can recognize a feature nonetheless.
It is quite likely that language arose from abilities of both visual and auditory systems. In any event, a non-linguistic-abled creature could have some intermediate level of consciousness, and certainly self-awareness.