Q: how to upload a video

To where would you like to upload the video?

iTunes on your computer?

iTunes on your iPad?

Seriously you need to provide details of what you want to do and what your ultimate goal is.

Otherwise its going to be very hard to provide accurate help.

To import a video to iTunes just open iTunes and in the file menu click on "Add File to Library".

iTunes 11 for Windows: Import music and video already on your computer

http://support.apple.com/kb/PH1612

Then navigate to the file you want to import.

As for iCloud, you can't directly upload videos to it. icloud is for App data and device backups.