How To Rotate Part Of An Image In Photoshop?

Go to image> image rotation> flip canvas vertical.

or did you mean (free transform)?
if free transform do this,

1. Double click the picture in the layer section to duplicate
2. Select move tool from the pallet section then go to image> free transform. Then at the edge of the picture there will be 8 square hold (ctrl) then drag one of does square.

Cropping an image mean selecting a portion of the image to work with. This tool is used when we have some extra (un-useable) area of the image. For example, we scan the document and it is scanned with some extra black area or white area, which is not the part of the image. We can use crop tool to remove this extra area.

We can use this tool by two methods. First select the crop tool from main tool box or Press C. The tool will be selected. Now, selected the area that you want to keep and press Enter, the area outside the selected area will be deleted. Second way is the select the area by using the rectangular marquee tool. Make a selection and from menu bar select Image -> Crop. This will give you the same result.

To rotate an image, we have also two methods. First is to use the free transform tool, to use this Press Ctrl + T or from menu bar Edit -> Free transform. The layer should be unlocked to use this tool. A rectangle box will be shown with boxes at corners and middle. Using these boxes we can rotate or resize the image.

The second way is to use the Image –> Rotate Canvas -> Arbitrary/180/90CW/90CCW option.