Best you include what version of Premiere Elements that you are working with and the computer operating system on which it is operating.
If versions 11 or 12, Applied Effects/Applied Effects Palette/Motion Panel expanded...in the Motion Panel is an option for Rotation. You can right click the video on the Expert workspace Timeline and select Rotate 90 degrees right or left.
If version earlier than 11, Properties Palette/Motion Panel expanded...in the Motion Panel is the option for Rotation. Same about right clicking the video on the Timeline, selecting Rotate 90 degrees left or right.
Please let us know if that targeted your question.
Welcome to the forum.
Also remember that when you do Rotate that portrait oriented footage, it will be used in the video frame, which will be horizontal, or landscape.
You will have black bars on the side. You might want to leave those, for that Clip, or use the Fixed Effect>Motion>Scale (see ATR's directions for where to find the controls), to fill the width, effectively "cropping" top and bottom, until the width has been filled. You can then use Motion>Position, to move that effective cropping up, or down, as needed.
It worked - now the full clip is oriented correctly, and I can use the footage as I intended.
Thank you very much.
Glad that the suggestion worked for you.
Excellent news. ATR gave you perfect instructions, and you followed those perfectly.
The orientation of footage, shot with a camera phone, CAN be a bit daunting, at first, but there are fixes, though they come with the caveat that I mentioned.
Since things are editing well now, I would urge you to list ATR's Reply as Correct, as that will let others know that you got the answers needed, so that they will read your post, to solve their problems, as well.
Adobe's Forum Team also monitors Correct and Helpful answers, to convince upper-management of the worth of the Adobe Forums.
Good luck, and happy editing,