I'm quite lame at rules of Polish grammar so I'll translate only your questions
Pan - Sir, Pani - Madam, plural form - Państwo
Jak sie Pani/Pan ma?
you always use Pan/Pani or Państwo when you want to talk to someone older you don't know
I saw you should be I saw you Madam/Sir in polish: Widziałam/em Panią/Pana
I gave you sth Madam/Sir - Dałam/em coś Pani/ Panu
Can I ask a question - Czy mogę zadać Panu/Pani pytanie?
you don't have to use capital letters, you can write pan/pani and it will be formal
but remember it's just my native speaker's point of view ;P