Row Count in Table = Cell Value

If you are willing to place your totals at the top of the table then it simplifies things greatly and avoids the unnecessary use of VBA code.

You only need to drag the cells down as far as needed to copy formulas and formats when new rows are required.

Optionally, format as many rows as you think you may ever need and let the table expand/contract based on the input cell. With the totals at the top of the table you don't need to scroll or accomodate any row insertions/deletions.

I would do this but there is stuff under the table that i would like to have, and the table has the potential of being from 150 to 500 rows long, so i would have to have the stuff way way down at the bottom.

second, im not sure how to have the header sum all of the rows i have.

say i have 5 rows, i put =sum(B3:B7) that would work, but i change the 5 rows to 8 rows, it would still say =sum(B3:B7), not sum (B3:B10)

I would do this but there is stuff under the table that i would like to have, and the table has the potential of being from 150 to 500 rows long, so i would have to have the stuff way way down at the bottom.

One cardinal rule of efficient spreadsheet design is to have all related raw data on a single worksheet and structured in classic database layout.
If the "stuff" at the bottom is not raw data, can't you relocate this to other columns/sheet and reference it?

second, im not sure how to have the header sum all of the rows i have. say i have 5 rows, i put =sum(B3:B7) that would work, but i change the 5 rows to 8 rows, it would still say =sum(B3:B7), not sum (B3:B10)

Create dynamic named ranges for the data columns and reference the named range in the SUM formula. Dynamic named ranged automatically expand/contract with addition/deletion of new data.

See attached for formula example and dynamic named ranges.