Birds can learn many many words. I believe there was a Budgie who learned an amazing 500 words....(I think).

Very pretty girl. Not Albino, though, so sexing her should be fairly easy. Differentiating genders are typically harder with Inos and a few other mutations.

Perhaps you can turn on the flash and take a picture of them again?

Currently, it does indeed look like a girl and boy. Generally, it takes up to two months after weaning to tell the gender for sure. Girlies tend to have light colored, whitish ceres as young 'uns. Males tend to have dark pink/light purple ceres as newly weaned chickies. Once the girlies hit birdie puberty, their ceres turn a dark chocolate brown (about 6 months to a year).

As for tips on training, one book: Guide to a Well Behaved Parrot by Mattie Sue Athan. Wonderful book!