Then the Lord said to Moses, "I will rain down bread from heaven for you. The people are to go out each day and gather enough for that day. In this way I will test them and see whether they will follow My instructions." Exodus 16:4
When God took the nation of Israel through the desert, there was one thing the people simply could not do outside of God alone: They could not provide for themselves. They could not plant. They could not harvest. They could not manufacture. It was a place and time where nothing but complete dependence was the rule. God gave manna one day at a time. The manna spoiled the day after, so they could never store it. They could not go to the manna store to get more. They couldn't start a manna business to capitalize on all the free manna. I can tell you from personal experience that when God takes you to the desert, there is nothing you can do to change it until He wants to change it, so do not strive against God in the desert place.
What was the purpose of this restrictive time in their lives? Why did God have to keep them from using any of these abilities to earn on their own? It was a season to build trust and reliance on God. They had relied on the "manna" of Egypt for so long that He needed to change their whole nature of looking to Egypt as their provider to looking to God as their provider. This boot camp was to be only for a season. However, what should have been less than a 30-day journey took 40 years because of the hardness of their hearts. They never passed the test God gave them.
Has God taken you into the desert? Is He forcing you to depend wholly on His provision? Pray that you will learn the lessons God desires you to learn in the desert place. He will bring you out when He has accomplished all He wants to build in your life. Remember that it is a season; you will not be there forever. He understands that no one can stay in a desolate place forever.