a barracuda had followd my lure but he didnt attacks
im new at this type of fishing but i had follow ups of fish but never attaking
Try changing your retrievel speed, and or mix it up, with some twitches mixed in. Something will get it excited to hit your lure.
Not sure about barracuda, but in theory for predators:
1) speeding, try to accelerate the retrieve when you see the follow.
2) stopping and wait. Sometimes they will just carry on and hit it.
3) stop and go/ jerk : mixture of movement/speed - just make it random.
I hope an expert (which i am not) will give you more tricks.
check other posts as this argument is very common