I'm answering the two issues raised in the original post:
1. Will God give something He doesn't wish you to have?
Using calling for ministry is a wrong topic: everyone is called to ministry.
2. Are there things He wants you to ask for?
He wants you to ask for authenticating signs for the ministry you do, prising people out of Egypt.
ALL OTHER WANTS ARE THINGS HE HAS WARNED NOT TO DESIRE, INCLUDING BREAD WHICH DOES NOT SATISFY.
John6:27
27
"Do not work for the food which perishes, but for the food which endures to eternal life, which the Son of Man will give to you, for on Him the Father, God, has set His seal."
Matthew 6:25-33
25Why are you worried about your life,
as to what you will eat or what you will drink; nor for your body,
as to what you will put on. Is not life more than food, and the body more than clothing?
26“Look at the birds of the air, that they do not sow, nor reap nor gather into barns, and
yet your heavenly Father feeds them. Are you not worth much more than they?
27“And who of you by being worried can add a
single hour to his life?
28“And why are you worried about clothing? Observe how the lilies of the field grow; they do not toil nor do they spin,
29yet I say to you that not even Solomon in all his glory clothed himself like one of these.
30“But if God so clothes the grass of the field, which is
alive today and tomorrow is thrown into the furnace,
will He not much more
clothe you? You of little faith!
31“Do not worry then, saying, ‘What will we eat?’ or ‘What will we drink?’ or ‘What will we wear for clothing?’
32“For the Gentiles eagerly seek all these things; for your heavenly Father knows that you need all these things.
33“But seek first His kingdom and His righteousness, and all these things will be added to you.
Now give an example of a prayer that asks for things that God has decided you should be better of not having.