How can I make damage factor sync with an entity's attack? (No Geckolib, No plugins)

So, I'm trying to make an animation where the enemy charges up a bite and then performs the bite. Overall it takes about 1.5 seconds to complete the animation.

I, however, wanted to make the attack dodgable, which is why I have the charging.

How can I sync when and IF the damage is dealt to the player, to the animation?