Hook on my truck is stuck

Which hook are you referring to? We need more information.

I am going to guess you mean hood. Have someone pull the release and hold it. Then take your hand and push down on the hood over the latch area, then lift up. Release the secondary latch.
If you pull the cable and it moves really easy it may be broken. That requires removing the grill panel so you can get to the latch. If you have not done that before you may want to take it to a shop, the grill is easy to break and the latch can be a bear to release.