I don't know what WP is referring to either. Where did you see it used? Do you mean SWP (i.e. southwest Pacific - Australia, New Zealand and a few other islands)?

From your other messages, it appears as though you are flying economy. This is booked in "L" class. Depending on what airline FF program you are in and what airline you are flying you will likely get either some fractional mileage credit (e.g. 50%) or none at all.

There are no direct flights from GIG to LAX. You would need to connect in MIA or JFK. You could work your way across the country via ORD or DFW and then do LAX-SJU. Also, there are no direct OW flights between SEA-LAX.

You need to download one of the electronic timetables from here or here to determine what flights are available on the routes you want to fly.