Originally Posted by saddlesore
My question is how do I rotate the pic 90deg
That depends on how the pic was taken and what the metadata says.
Modern phones & DSLR's will store metadata info in the pic about the camera's orientation when the photo was taken. This is why it can get confusing when attempting to rotate an image within a paint program as many just store the metadata and write it back out with the image when the file is saved.
I usually use a tool to strip out jpeg metadata and then rotate the image as appropriate (one free tool I've used with success in Windows is the Fast Stone image viewer: FastStone Image Viewer, Screen Capture, Photo Resizer ...
-- not affiliated with them, just a user. On the Tools menu there is a "remove jpeg metadata" item).
I know this sounds overly complicated other than simply just "use X and rotate by 90 degrees"....modern problems.