Macro to derive based on cell matching values

Dear Everyone,

I would like to get a macro that derives a specific values based on the cell matching values. Attached a spreadsheet that contains two tabs;

Audit:
AuditID
SubjectID
Query Text
Action Type

Source:
Check Name
Query Text

When the query text column on both tabs matches around 50% then Check Name must be derived and also for the check names in 'Source' where there are no matching in 'Audit' that should be derived as No Query Fires.

Even if its possible in VLOOKUP we need a macro as we have more requests following up with these sheets.

It would be great of help the reply is very details as steps, since am very very new to macros and trying to learn basics of it.

Thanks