Manna (Exodus ch.16), sometimes quail (Exodus 16 and Numbers ch.11), and - if they wished - their own livestock and/or its milk and cheese. Also, they sometimes were able to purchase things from peoples in or near the wilderness (Talmud, Yoma 75b).
Exodus and Joshua both mention the food eaten.
The Jews spent 40 years in the wilderness.
The Tabernacle (Mishkan), Exodus ch.25.
Amalek (Exodus 17)
A pillar of fire (Exodus ch.13).
God provided for them (Exodus ch.16 and 17).
He did not. He fasted the whole time while he was on Mount Sinai (Exodus 34:28).
It was the route God chose for them to the Holy Land (Exodus ch.13).
The first wilderness (not"desert") which is mentioned after the crossing of the Red Sea is the Wilderness of Shur (Exodus 15:22).
The Torah states they were fed a substance callled Manna (מן), pronounced "mahn" in Hebrew. Exodus ch.16.
The Biblical text (Exodus ch.16) describes a food called Manna.
God provided it (Exodus ch.15 and 17, Numbers ch.20).