Yes, eat in Windjammer buffet, or at Sorrentos for pizza (free) or at Johnny Rockets for burgers $3.95pp supl. Or you book speciality restaurant Portofino $20pp supl.
I normaly travel P & O i have noticed you have to pay for alot of the eating areas are there only a small amout of eating areas free.
No problems with sun beds on Voyager class ships. Main Restaurant has first & second sitting (Waitered). This is requested at the time of your initial cruise booking. Further to that there is the informal self service (Windjammer)No Charge, Portofino's (Italian) $20 charge, Chops Grill $25 charge, Johnny Rockets (50's style Burger Bar) $3.95 charge. Promenade Bar (Pizza's, cakes & buns) No Charge. You will not go hungry however you dress.
Food as per comments below, but as for sun beds there is no problem UNTIL the last day when everybody is on board,you will struggle a bit then so I would sugest getting there early if lounging in the sun is your thing.