Help with Vb program

Im currently taking a Vb class and am having difficulty writing a function portion of this assignment. is it possible that someone could help me?

A salesperson earns a weekly base salary plus a commission when sales
are at or above quota. Create a project that allows the user to input the
weekly sales and the salesperson name. calculates the commission. and
displays summary information.
Form: The form should have text boxes for the sales person's name and his
or her weekly sales.
Use constants to establish the base pay, the quota, and the commission
rate.
The Pay menu item calculates and displays the commission and the total
pay for that person. However. if there is no commission. do not display
the commission amount (do not display a zero-commission amount).
Write a function procedure to calculate the commission. The function
must compare sales to the quota. When the sales a re equal to or greater
than the quota, calculate the commission by multiplying sales by the
commission rate.
Each sales person receives the base pay plus the commission (if one
has been earned). Formal the dollar amounts to two decimal places; do
not display a dollar sign.
The Summary menu item displays a message box that holds total sales,
total commissions. and total pay for all salespersons. Display the numbers
with two decimal places and dollar signs.

Test Data: Quota = 1000: Commission rate = .15: and Base pay = $250

I have screen shots of the code i have so far

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