Does the U.S. military have the means to spend a lot more than the allotted budget for the military?

Does the U.S. military have the means to spend a lot more than the allotted budget for the military?

A black budget or covert appropriation is a government budget that is
allocated for classified or other secret operations of a nation. The
black budget is an account expenses and spending related to military
research and covert operations. The black budget is mostly classified
because of security reasons. The black budget can be complicated to
calculate, but in the United States it has been estimated to be over
US$50 billion a year, taking up nearly 10 percent of the US$700
billion American defense budget.[1]

https://en.wikipedia.org/wiki/Black_budget

Now, 10 percent isn't much and makes me think that the black budget isn't used to hide how much the military is spending, but on what it is spending. Now, the question is whether the military or the government has a mean to hide a much higher figure like $300 billion, which would be roughly half without anyone noticing. Is the U.S. government spending and budgeting scheme allow for such spending to be unnoticed by the public?