Asking on behalf of a traditional independent priest in India.
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Wine is very easy to make. You press the juice out of grapes and allow it to ferment. You want to put it in a clean container and seal it with an air lock, such as you can get at any home brew store.
You don't even need to press the juice yourself. You can get raw grape juice at a local winery and use that. I don't know if they have wineries in India, but that's how you do it.
Some priests grow their own grapes and make their own wine. The grapes naturally have yeast on the skins, which gets into the juice when you squeeze them, and causes the sugars to ferment. I would recommend using a hygrometer to measure the alcoholic content, since you want to be sure it is wine before it is used for Mass. I think the rules say the wine should be at least 8% alcohol (normal table wine is 12-14%, so this is on the low end).
I would suggest he go to a local home brew shop, if such things exist there, and ask them how to make his own wine. But really, wine is not difficult to make, which is part of the reason God used it for the Mass.