In this video Tutordidi will teach you how to rotate video in kdenlive.

To rotate the video first import/ add in Kdenlive. Once you got it drag and drop it from project bin on timeline. To check the video click on the play button on project monitor. To rotate the video click on effects tab then click on video effects option in the search box type rotate (partial text will be okay) from the list click on rotate (keyframable) drag and drop it on video on timeline.
Now click on view menu click on properties to open properties window to rotate the video drag Rotate X option all the way to the right. That’s it. Your video will get rotated.