This is the 304th most frequent Russian word.
израиля
"Израиля" means "of Israel" (genitive case of "Израиль").
Here, "Израиля" is used in the genitive case to indicate the origin of the letter.
Я получил письмо из Израиля.
I received a letter from Israel.
"Израиля" in this sentence shows the starting point of a movement, demonstrating its genitive case usage with the preposition "из".
Моя подруга приехала из Израиля.
My friend came from Israel.
In this context, "Израиля" indicates possession, as it describes the culture belonging to Israel.