I have mostly cruised with P and O
the vast majority of passengers are British and they price things in pounds on board. I like freedom dining, I don't know whether you have chosen fixed time or freedom I've done both, freedom just means you turn up when you want to eat but sometimes they give you a pager if there is no table available, you don't normally have a long wait maybe 30 minutes is my maximum wait.
Your cabin steward will provide you with extra coat hangers, ice or extra toiletries, just ask.
I don't usually eat breakfast at home but I do like room service breakfast when I'm on the ship
Every evening you'll get a copy of a what's on guide for the next day, it'll tell you what time you dock, when to be back on board and all the entertainment, it's worth reading but don't be like me and re read them when I get home and find lots of things I've missed