Thanks a lot for all this great advice.
At this stage, I need to arrange the travel from Brisbane/AU to Saint-Jean-Pied-de-Port. I will search here, but I need advice on
what would be the best route. From Brisbane to Spain( Madrid or Barcelona) or France (Paris)? Then how to get to SJPdP from either of these cities? and then the way back. That is giving me a headache LOL.
It is difficult to tell, without knowing what evaluation criteria you are thinking of, what might be 'best'. Certainly all the entry point options you are considering, Madrid, Barcelona and Paris, are workable from Australia. I have gone through both Barcelona and Paris to get to SJPP. This year my wife and I will fly in through Madrid, but not to walk a camino unless I can get a short leave pass at some stage while we are in Portugal.
I have found the next important question is whether you want to return through these same airports, eg to take advantage of a cheaper return air fare deal, or you have an open jaw and return from somewhere else. Again, I have done both, and both options are workable.
If you don't feel comfortable doing the booking yourself, find a good travel agent, preferably one who has some experience working with pilgrims and who isn't going to try and arrange every element of your trip. You don't, normally, need or want them to do that. They just need to get you to somewhere where you are comfortable taking over, and get you back, typically from SDC at the end of your pilgrimage. On my first camino, that was just to get me to and back from Paris. I managed the connexions from CDG to SJPP, and from SDC back to CDG with a short stay in London. More recently, online booking engines have improved to the point where I no longer feel the need to use a travel agent. When I flew into Barcelona, I had an open jaw to LHR and filled in the other bits when the time came.
More, as
@trecile has already said, there is a wealth of discussion already here on the forum about the very options you are considering. You should find plenty to think about and help make any decision about which way to go.