I also used Emla cream on my port it was supplied by the breast care nurse. You can also buy emla patches from the chemist. My oncologist recommended them as less messy than the cream .I bought two and didnt realise they cost 7.50 each otherwise the cream was free.
AS for food I ate a normal diet. I was served lunch during chemo which was fine. If at times I had chemo out of lunch hours I always brought snacks with me. Fruit nuts sultanas maybe a sandwich. Whatever you feel like.
I was encouraged not to loose weight (first time ever) and eat normally.
Accessing the port was okay even without the cream . It did sting but only briefly. good luck