This is Isaac's blessing. He thought he was speaking to Esau, but he was speaking to Jacob.
Here "you" is singular and refers to Jacob. But the blessing would also apply to Jacob's descendants. (See: rc://en/ta/man/translate/figs-you and rc://en/ta/man/translate/figs-synecdoche)
dew of heaven
"Dew" is drops of water that form on the plants during the night. This can be made explicit in the translation. AT: "night mist from heaven to water your crops" (See: rc://en/ta/man/translate/figs-explicit)
fatness of the earth
Having fertile land is spoken of as if the earth were fat or rich. AT: "good soil for producing crops" (See: rc://en/ta/man/translate/figs-metaphor)
plenty of grain and new wine
If "grain" and "wine" are unknown, this can be stated more generally. AT: "plenty of food and drink" (See: rc://en/ta/man/translate/figs-explicit)