When the nation of Israel was in the desert they needed something to eat. God supernaturally provided a substance called manna. It sustained them for forty years while in the Sinai Peninsula.
Although the Bible describes manna, the explanation leaves me wanting. Apparently it was a nutritious foodstuff. It had multiple uses and physically nourished them, either in part or in whole, while living in the desert.
Read about manna in Exodus 16:4-5, 15-32.
For the four decades that God’s people were in the desert, he provided manna for them to eat. Once they left the desert and arrived at the land God promised to give them, the manna stopped (Joshua 5:12).