Why can't you keep your thoughts and concepts coherent for even two sentences in a row? Yes, a flat tax is regressive and it is exactly what Lewk called for. A percentage of income tax is a proportional tax (and yes, its structure can still mean it has a heavy impact on those who can least afford it. Really, even the most progressive graduated tax scheme is still going to more heavily impact those with less money, all that can be done is to try and minimize that impact)
Flat tax: Everyone pays the same nominal amount, say $2,000. This is Lewk's desire. Sales and excise taxes are flat taxes though the language they are couched in will confuse some people into thinking they're proportional.
Proportional tax: Everyone pays the same percentage of their income, the same proportion, say 15%
Graduated/progressive tax: People pay differing proportions of their income depending on how much they earn, proportions typically/ideally increasing as their total income increases. What is actually used.
If you reduced the budget by 90%, that's still going to be 2,2000 dollars per person per year (actually more, I didn't bother culling the kids out of the population data). Which is going to be more than anyone who only has part time work (or even full-time work at minimum wage) is going to be able to pay, particularly with spiking housing costs.