When I activate a squad with the Yvaris Nebulon-B and I choose my target to shoot it if I kill it do I lose my second shot or can I move? I didn't have another target in range to take advantage of the second shot.

You can shoot or move in any order when activating squadrons from a squadron command. Therefore, I'm reasonably certain, although I haven't read the Yavaris title card in reference to typing this, that you could indeed still move after shooting. Pretty sure its worded something like "can give up their move and shoot a second time."

Yavaris: Squadron dial/token. Each squadron you activate can attack twice if it does not move.

You can only shoot twice if the squadron does not move. They key word is can.

Rules Reference page 12 under "Squadron Activation" says you can move or shoot in any order

After you activate your squadron with Yavaris. You can shoot your shot. And then shoot again or move. You get to choose the order. So long as you did not move, you can shoot a second time and it can be a different target.

Just used the Yavaris title card in a game this past weekend to very good effect. Definately situational, but in the right conditions the ability to shoot twice and give up the move part of a squadron command can be very useful!