Hi

First, why would I buy a property for 10 million euros? This is a huge sum if it is only intended for residence.
Secondly, French law does not provide for the right to obtain a residence permit in France in exchange for the buying a property.
This is a fallacy that you have to be cautious of, because the granting of a residence permit passes according to procedure that must be respected as well as the discretion of the consul even if the person owns a property inside France. But it can be pointed out that owning a property in France can help the person getting long residence duration as a visitor. And we reaffirm that it only helps and does not guarantee residence.
A long visit residence is granted to people who demonstrate that they have the financial means which makes them avoid any work activity in France. The source of the money to buy a property in France must also be proven, as the French authorities are aggressively fighting smuggling or money laundering.
Regarding obtaining a visit visa for a wife, you can consult the Directorate of Residence and Immigration in France to obtain a family visit visa in France and the origin of your marriage certificate must be accompanied with your application.