Urgent Help With Form Code Please

ok what follows is a kind of pseudocode of what I'm trying to do. It would really help if someone could tell me how to get a command button to do the following startin by the copying of fields into a new record in a table and then using that table to do the required actions. Any help would be greatly appreciated and yes it is urgent as the assignment is due in on Wednesday.

Copy fields into new record in table Transactions
If [Transaction.In or Out] = In Then

[Items.Current Qty] (for specified Part No.) = [Items.Current Qty] + [Transaction.Qty]

(Add new record to Purchase Orders Table)

[Purchase Orders.Purchase Order No] = [Transaction.From/To]

[Purchase Orders.Part No] = [Transaction.Part No]

End If

If [Transaction.In or Out] = Out Then

[Items.Current Qty] = [Items.Current Qty] – [Transaction.Qty]

(Add new record to Sales Orders)

[Sales Orders.Part No] = [Transaction.Part No.]

[Sales Orders.Sales Order No.] = [Transaction.From/To]

End If