Do you know your biopsy results and what chemo you'll be having? You may bexwell enough to go but you may want to postpone for a month to be sure you feel fit enough. Thete is a short break between chemo and radiotherapy of about 4 weeks. We are all diffetent and you won't know how chemo will affect you until you doit.
There may be travel insurance issues you might need to look at also. I know other ladies here have info about that.
It's a lot to take in at the beginning. No question is silly so ask away.