1) if I encounter an event that don't have a discard condition, is it stay for the all game?
No Event stays in play for all game. Events are always discarded after resolving them; Events that last more rounds (e.g. Blizzard, Prophesy, etc…) are put on the space and count as faceup cards for that space untile they are discarded.
Could you please mention which Event has no discard condition?
2)if I encounter a lunar event that change the time card to night and in the same turn also a lunar event that change it to day what should I do???
You encounter the cards in the order they were drawn. You first flip the time card to night and then flip the time card to day. The first Lunar Event won't have a big impact on game, but still it causes the time card to flip to Night side for a few time.
Adventure Cards must be dealt with in the order determined
by their encounter number (the number at the bottom right
corner of the card).
The lowest number is tackled first, then the next lowest, and
so on. In the case of a tie, the character encounters Adventure
Cards in the order they were drawn.
3) if I have the object that say that in the end of my turn I need to discard all the cards in my space, is this apply to events to???
The Hungering Artifact eats all Adventure cards on the space. This includes Events that remain on the space.