Please Note, the game is in over a week of development so not much is done.
There is no First Person view currently, although we do plan on adding the option.
Yes, you are able to save your builds by pressing 8, and you can load your builds by pressing 9.
There are no guns yet but they may be added.
The hunger/thirst system will be coming in the 1..2 update.
There is a day/Night cycle.