Note: I am speaking for the United States only (the hospital industry differs greatly around the world).
Individual people almost never own hospitals. Because of the huge investment required to build or buy a functional hospital, and the legal requirements the hospital must meet, they are usually owned by large companies or are not owned at all. In the United States, roughly two-thirds of the hospitals are non-profit organizations without any owners, and other third is split evenly between government hospitals and for-profit hospitals owned and operated by large professional companies. (I don't have a source for these numbers, so please do some research to check this before relying on it). A good example for a for-profit hospital management company is Tenet.
I'm interested in understanding what you like about owning a hospital and what you like about being a Nurse. They are each very very different activities, and it's exceptionally unlikely that you could do both at the same time. Being a nurse will bring certain types of experiences, and will require years of nurse training, whereas managing (not owning) a hospital will require business accumen built from years of management training. You could certainly do both, but I can't imagine how you could be able to train to do both at once, nor would you be able to fulfill your nurse duties (which is a full-time job with a demanding schedule). If you would like to be a nurse but want to have some small ownership stake in a hospital company, you could become a nurse and use your savings to purchase shares of Tenet or another similar company on the stock market, which would give you a small ownership stake in the hospital industry without being a hospital manager.
If you would like to clarify, please do so in a comment or re-edit your question, or ask a new question!
Good luck - Jared from the CareerVillage Team