Extracting data from a table based on a common entries with another table

Hi there, I am hoping I can get help to solve what is probably a relatively simple problem

I have a MAIN table with 120 rows and 8 columns - which is updated often. The FIRST column is critical since it contains a CODE that identifyies each row.

My question is, how do I extract rows from the MAIN table into a smaller table - with a column of say 10 codes that match the CODES in the first column of tha MAIN table.

I'm sure it will be just a simple piece of code to compare each CODE in both columns and when a match is found, place that row in another table.

I hope this makes sense, any help with be much appreciated.

Shannon