ipad mini4 16gb have avalible storage?

Yes an iPad Mini 4 16 GB has some storage. But that model has the least amount of storage of any model. What exactly is your question?

Available storage on a 16GB iPad device would be about 11.9GB under iOS 9.0.2. This is what both of my mini 2's and my Air 2 show. The mini 4 is basically an Air 2 in a smaller form-factor so I would expect the same free storage space.