At the age of 35, approximately 2500-2600 years ago.
You have to attain enlightenment, but you have to work out how to do it for yourself. Otherwise you are just an Arahant.
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The Buddha taught that enlightenment can be reached through, Meditation, Contemplation, and Mindfulness while acting compassionately for all beings.
Because it is the doctrine that Buddha provides to us to follow to attain enlightenment.
No, Buddha himself is not worshipped, rather Buddhists attempt to attain the state of enlightenment that Buddha himself achieved.
Yes, for a part of his life after he attain enlightenment.
A buddha is someone who has found out how to attain enlightenment for themselves. An Arahant is someone who was told how to do it by someone else.
The Buddha wanted to attain enlightenment. He had set out to find himself and once he did he set off to spread his findings to others around the world.
Buddha is a status or a symbol. If you attain enlightenment in the highest order you become a Buddha. For the past billions of years there are a lot of Buddhas. Prince Siddharta who became a Buddha 2500 odd years has a son named Rahula. The question of 'who is buddha baby' is not specific enough for any answer.
His achievements for us were that path to the cessation of the cycle of death and rebirth was identified. So suffering and pain could be avoided. For himself his achievment was to attain enlightenment.
A Buddha is one who has worked out how to acheive enlightenment, and a Bodhisattva is one who is about to achieve enlightenment.
Enlightenment.