Jesus taught his disciples to ask God for their daily bread, that is, the food they needed for the day.
Just as God provided manna for the Israelites in the desert, the implication is God will meet our needs each day.
We are not to ask for enough for the week, the month, or the whole year, but for only one day, today. Tomorrow we will need to ask again.
The instruction to ask daily isn’t because God is only powerful enough to supply our need for one day, but because God doesn’t want us to take him for granted. And if we seek him each day, that’s not likely to happen.
Plus, I think he enjoys hearing from us each morning.