At first glance the Lookup Panel in FRLogger resembles the Log Entry panel. The purpose of the Lookup Panel however is to allow you to lookup a station without the intent to log that station as a contact.
Like on the log entry panel, enter a callsign into the call field and press the TAB key. Assuming you have QRZ or HamQTH lookups enabled the lookup fields should populate with data provided by the lookup service.
If you had worked this station before then the log list below the lookup fields will show your prior contacts.
There are buttons below the call field to open QRZ or HamQTH websites from the call sign.
Lastly if you decided you were going to work this station you can hit the "Copy to log entry" button and all of these fields will move over to log entry so you can log the contact.