A prediction: there will be a late-April government shutdown

[Recursion]

3. He sort of can

Can he downsize agencies without congressional approval?

He can (and apparently is in the process of doing this) refuse to fill political apointments, which means the agency is pathologically understaffed and incapable of actually doing anything (though it's a losing move on his part, since it leaves the career employees with more levers to pull; however, he's a moron, so he doesn't get that).

However, he doesn't actually have a direct line to an "off" spigot for money that Congress has authorized and appropriated, in a general sense.