Can my parakeets live outside
Yes, ichibanarky is right. Also, if you have their cage outside, make sure it's not in direct sunlight during the day. It could be partially in the sunlight so your parakeets can go sun themselves in the sunnier part of the cage when they want. Or cover a part of your cage to give them some shade.
I don't think they'd survive outside during winter though, they should be kept inside.
If they were raised in captivity, then letting them loose would not do them well.
If you mean putting the whole cage outside, then they'd be fine as long as it doesn't get too hot or cold, and it's out of reach of predators.
why? and it bed to keeep them in