In what way do you need help? Do you have something but you're not sure how to implement it? Because rotation and hittest are essential for these kind of games, which I'm sure you've realised
In any case... what you'll probably need to do is keep a list of every enemy, and run some hittests on them...
So ok, Attach your bullet like usual, and now let's take care of how it will move
Usually we just think of a value like 10 and add it to the current X to make a straight shot, but when we have an angle, it's different. Let's create two variable that will calculate how much we have to add to the X and Y to create a 10 speed in a line that's not in front of you. Let's call it progression.
And since it's easier, let's code this inside your bullet
ProgressionX = (Math.cos(_parent.rotationindegrees * Math.PI / 180) * Your Speed); ProgressionY = (Math.sin(_parent.rotationindegrees * Math.PI / 180) * Your Speed);
Having this, outside the loop of the object, will grant these values the exact moment the bullet is created, so it will keep the perfect progression of that angle