OK - I'm back. OK, for protein it says the RDA is 48/44 and I'm not positive, but I think that's max/min maybe and that means 48g/44g? Forget about protein/fat/carbohydrates for a minute because we're talking multi-vitamins here.
So, since you're 18, and a woman the things you should be thinking about are calcium, iron, and folate. I am NOT recommending you go run out and buy those things, but when you're looking at the multivitamin look for those things.
Folate: women of childbearing age should take in 400micrograms of synthetic folate in addition to the folate that occurs naturally in their foods. (that's from the DRI committee, not me making things up.) The reason women need more folate is because folate deficiency is associated with neural tube disorders which are very serious birth defects such as Spina Bifida. These can happen within the first days/weeks of pregnancy even before you know your pregnant.
Calcium: Women are especially at risk of osteoporosis. I know when we're young we don't think about diseases that might hit us when we're "old". But, the calcium you take in NOW is very important because at a point your body stops producing bone mass. So, if you wait until you're older and then said "Oh crap." it's already too late. You should take in 1000 mg/day.
Iron: Again, because we're women we're more at risk for iron deficiency because we lose a lot of blood each month. Be careful with iron supplements though. Excess iron is just as bad (if not worse) than too little iron. If it's part of a multivitamin it's most likely not too much. You should take in 15mg/day
Those are the three most important vitamins for women. The rest are important as well, but those are the ones you should look at in a multivitamin. Also, (required disclaimer lol) you should be getting the majority of your vitamins and minerals from your diet. Eat lots of
fresh fruits and veggies and you'll be doing great.
Keep your plate colorful

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