You (The Absolute or Life Itself) are already enlightened; “you” (the I/ego that asked about ‘thinking’ whether or not it is enlightened) can never be.

The always-enlightened Self never asks ItSelf, or anyone else, if It is enlightened. Fully ‘awakened,’ enlightened, self-realized, liberated, or what ever term you like, is it’s only possible ‘state,‘ because It is everything, and the nothing behind that everything.

The illusion (ego/mind) deals in concepts and thoughts. In your case, it has turned enlightenment, liberation, courage and freedom, all into concepts and is considering if it can ‘think’ itself into enlightenment, or if ‘others’ will think so, too.

Belief is also useless in enlightenment. You can ‘believe’ you are free & enlightened all you want - sort of that ‘fake it till you make it’ attitude - or believe that believing it will somehow ‘make it so,’ or at least, accelerate the process. But true enlightenment is not ‘cause-&-effect’ and nothing the ego can do - thinking, studying, practicing, mimicking, acting on it, believing, disbelieving - will ever ‘cause’ enlightenment. Believing something is that poor perennial substitute for actual Reality.

You have to be careful to take what NIsargadatta said in context, and not overly-literally. Even though both he and Ramana Maharshi said things like “Believe you are in bondage and you are in bondage, believe you are free and you are free,’ both would immediately admit their enlightenment did not dawn simply as ‘cause-&-effect’ from thinking about it or believing it, really hard :-).

The phantom thing (a ‘separate me”) that thinks & believes is the very thing that must disappear in order full enlightenment to be realized. If that dawns for you, you will never identify with or give much credence to anything you believe and most of what you think, ever again