I know this is in the rule book so if somebody could point me for the life of me I can't find it.

I am trying to find out when a squadron would activate when the squadron command is shown. Is it right away? or can the ship attack first and then they can activate the squadrons?

Immediately.

RRG, Page 3, Commands:

• Squadron: Resolve after revealing the ship’s command dial.

In Rules-Speak, that means, "Immediately after revealing the Command dial.". You have no opportunity to Shoot or Maneuver before the Squadrons Activate - they Activate before everything else (although, if you are resolving a Squadron and Engineering Command at the same time because you had a token, you choose the order of those two commands - Squad->Eng, or Eng->Squad, as they have the same timing).

As a Note, the whole point of the "Flight Commander" upgrade is to allow you to wait until after your maneuver.