Hmmm, I don't think so. Hospitals in Europe aren't like ones back home. They're not really amenable to shadowing, volunteering / candy-stripping, or whatever else. They can also be short-staffed with fewer resources, so wouldn't really have people with the time to show you around. If you know doctors personally over here, you could ask if you could shadow/observe them, but otherwise those things are usually for med students / other health students in rotations. Depending on where you're going, you can try emailing or calling certain hospitals and seeing, but the whole volunteering thing isn't really done, from what I can gather. Unless you get a job as a care assistant or transporter, but then you'd have to get a work visa, etc.