🚀 go-pugleaf

I have been trying to write a macro in Excel (so far unsuccessfully) 
to do the following for a large (3000 row) database in Excel:
The user would put the Item # and quantity in the CRITERIA range.

The macro that I need  would then:
do a search for the Item # in the DATABASE, select the DATABASE item 
quantity, and update (add or subtract) the quantity
with the quantity from the CRITERIA range. It would then get ready 
for the next input of item # and quantity in the CRITERIA range.

Any ideas as to what function I should utilize?

Please, PLEASE help!

Also please reply to roskar@jhuvms.bitnet as this account on unix is $$.

Thank you all so much.
VELJKO