Hi. My aim is to attract girls. Im in last year of high school.
I want to be confident even though I’m confident but who can deny more confidence 
and I want to attract/seduce girls.
Which is a better choice? What are their purposes anyways and which one should I buy
They are both quite viable - individually or together.
IG is a smart/youthful status product, whilst IS is a happy/feelgood mix.
Neither of these contain Androstenone, so no great sexual impact. If you are looking for a seductuon product, consider Ammo - in either its standard or Summer forms - At 24 you can use a bit of None but if the girls are younger, think on Summer as it has extra buffering that helps you around young women.
Beautiful description by expert.
Neither is better; each has its own role. IShine makes you look and feel like a fun guy to be around. IG makes you look and feel socially smooth (in a platonic way; see above). If you can swing it financially, get both. While they won’t do so hot with picking up ladies, these products used together are great for job interviews with most companies. Use only IG, without IShine, for more formal industries, like finance and government.