Which is why Zero actually has a point if he invokes the 14th amendment. Congress effectively already raised the “debt ceiling” when they approved the continuing resolution back in April.
No, the two things are not the same. Appropriations and incurring debt are addressed as separate powers in the Constitution, although both powers are held by Congress exclusively. If Congress authorizes the Executive to spend up to $2T, but the IRS only receives $1.5T in taxes, then the Executive must go back to the Congress and ask for authority to borrow the additional $.5T. If they do not receive that authorization, they must reduce expenditures to fit within the revenues available.