how to infer hyper registers i my design?

Hyper registers are not explicitly inferred. They Hyper Retimer makes decisions about whether it can move existing registers in your design from ALM locations to hyper register locations. There is lots of training about this:

https://www.intel.com/content/www/us/en/programmable/support/training/catalog.html?courseType=Online&language=English&keywords=hyper