It's RNG/luck dependant yes but there are factors you the player can do to make the odds more favorable.
Such as using items like the Destiny Knot, Everstone and Power Weight items to make the IVs and Nature more coherent
As for shininess you can affect that using the Masuda Method.
However speaking as a veteran player what your friend is asking for cannot assuredly be done in a given timeframe.
Yeah you can probably get the natures and IVs done today even, but shininess even with the Masuda Method is completely RNG dependant, there is absolutely nothing you can do to get a shiny Pokemon definitely within so-and-so time, it's completely random, it could take you 10 minutes to hatch one, it could take you 6 years to hatch one.
It's like winning a lottery, the outcome cannot be predicted