Step 1 ( get a chart of total order amounts with one chart bar for each day for a two week time period)
Define a summary field, sOrderTotal as the total of amount.
Set up your chart with:
Order date on the x axis
sOrderTotal on the Y axis
Use data from current found set
Show data points for groups of records when sorted.
Perform a find for all records in your biweekly time period. Sort them by Order Date.
Step 2 needs more clarification as to what you want to see on the screen, but there are several ways to modify this basic set up to show more than one chart at a time. If you add a field that identifies each record's Bi-weekly time period, you can even put this chart in a sub summary part "when sorted by" this same added field, then sort your records first by this new field, then by order date.
There are also ways to do this with portals.