None of them are necessary but a good whey protein is probably a smart investment. Count your protein ingested daily for a week or two to get a feel for how much you actually consume. If its nowhere close to what you hope it should be, use whey. If its sufficient without, don't bother.
Fish oil and multivitamins are good for general health. I use creatine and its cheap as hell so if you want that couldn't hurt. The rest is preference but IMO most supps beyond creatine are a waste of money unless you are a serious competitor.