If you can get to Steam enough to buy it under your account, then you can load it onto your new computer after you get that new computer.  Steam will ask you to confirm the new computer being used and then you are good to go for all your Steam games.

It's not going to affect what you already have on your account.

My next question can i give away my galactic civilizations 3 game from the game pack.

I ran into this issue in an earlier GalCiv bundle.  I wanted to gift someone a copy.  Steam wouldn't let me buy what I already had.  We had to log in to Steam under his handle and then let me pay for it with my card.  Not ideal, since it depended on both of us being local and ruined any surprise factor,, but that is what I did.

As part of a bundle or standalone? The change I'm thinking of only affects bundles, and was only introduced in March or so.

And what I am suggesting, based on what I have read, is that you will not get a second copy of the game, and the bundle price will be discounted accordingly.