Why don't I have portrait mode on my new iphone 7? potrait mode in future update on my iphone 7?? in future update on portrait mode on my iphone 7? in future any sofrware update on my iphone 7 to portrait mode??

The iPhone 7 does not have the hardware to support Portrait mode. Portrait mode require the dual camera that exists on the iPhone 7 Plus, and the iPhone 8 Plus. There is no way that software could upgrade the iPhone 7, it does not have the hardware.

If you want Portrait mode, sell your 7 and buy the 7 Plus, 8 Plus or X model.