That's a pretty broad issue you have there.

Since you're new to VBA you should play around a bit with the
recording feature to get a little closer to the final solution then
come back when you get stuck.

If your user is entering the data on sheet1 and you want to be able to
export a hard copy you might try simplying your issue a bit. Try
using a sort and filter. If you apply a sort on column "C" then do an
advanced filter on column "B" to only select items with "123" or "999"
then I think you'll have your basic format.

Hope this helps point you in the right direction.