The answer to that is a bit deeper.
Nibbana is attained by removing the ten “bonds” to this world (samyojana).
Breaking those bonds is done while one lives human life, whether as a Bodhisatta or just a normal person. A Bodhisatta learns the way by himself. All others follow that path found by a Bodhisatta.
– Not all humans are the same. They have flaws. A Bodhisatta (who has made preparations for the attainment of the Buddhahood over an unimaginable time) would have fewer flaws than most other humans. Each person’s current life (health, wealth, etc.) depends on past causes. But as long as one can cultivate sufficient wisdom (panna) by learning Dhamma, one would be able to break those “samsaric bonds”.
– But in the end, once those bonds are broken, they all achieve the same goal, i.e., not be reborn in any of the 31 realms. That is what Nibbana is.
It may be a good idea to read the following post regarding Bodhisattas:
“Pāramitā and Niyata Vivarana – Myths or Realities?”
Eventually, answers to questions of this type require a bit more advancement on the eightfold path.
– I am not trying to evade questions. But the point is that no matter how intelligent a person is, that does not count much towards making progress in learning Buddha Dhamma unless one understands the basic concepts. I have some friends who are scientists but are not able to understand some concepts. I hope you are different. You are at least curious. Some of those friends of mine do not show any interest. They are too busy!