WordPress comes with a built in media storage area. Images, videos, pdf files and audio files can all be uploaded here and placed into any part of the website. Bear in mind it may be more efficient and the video may play faster if you upload a video to youtube and then embedding it into the website.
To access the media library, login to wordpress, and click media on the left.
Here you can acess all previously uploaded media, and add new by clicking add new, and dragging and droping or browsing your files.