Not all Ibizas came with bluetooth. Our 61 plate one has just the regular radio/cd player.
There's a few old threads on here about retrofitting media interface boxes, but it appears a convoluted process involving different trim bits, a box, an adaptor lead, and then coding things using VCDS - and that might not even get full bluetooth capability.
You can get surround adaptors from various places for either single or double din radios, likewise wiring loom adaptors from a generic stereo ISO connector suit the particular wiring in the
Ibiza.