They should purchase garlic already minced. It is sold in jars at the grocery store.
I tried to cook with garlic for a long time before a website about garlic explained how. Garlic is mild when it is used whole surprisingly, that is how “40 clove roast” recipes can get away with that. Chopped it is much stronger.
Well of course I had that much figgered out but didn’t take it all the way.
The easiest way (assuming no boots) is to get a wide thick blade and chop coarsly and cover with salt. Mash/chop by drawing the flat of the blade over and over until you have a paste, the salt keeps the juices. A little goes a long way this way.