The order of the events is the following:
1. Siddhartha is Hindu prince
2. Siddhartha sees sickness, old age, death
3. Siddhartha sees a holy man
4. Siddhartha becomes religious seeker and ascetic
5. Siddhartha meditates under Bodhi Tree
6. Siddhartha finds enlightenment
If you want to illustrate more with the events, you can watch the movie <em>Little Buddha</em> (1993).