Enhance Effects how does it works?

You can re-roll those 3 line effects, the 'Option counts' refers to the max of line effects you can lock, by clicking a line effect you can lock it so when you re-roll the weapon this one locked will remains the same, you would need more Energy Converters for more line effects locked.

As you're new, I recommend you to take a look on the Mega Guide in the Guides section.