Basically, he means IVs/natures don't matter much for ingame, and it would be much easier just breeding after you finish the basic story and have access to dittos.
IVs... if you didn't get that, are 0-31 numbers that kind of determine the base stats of the pokemon, and you can't really determine them at low levels. You can do lv100 wifi battles with others, check stats, and then calculate what your IVs are from there.
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