Many people download video from internet and then upload again with different title but this is not legal and this is copy right issue and owner of this issue can put a sue on you to use this digital content created by him without his permission.If you want to use videos and images from net then you need to look for either public domain images., video etc or you need to search with creative common word so that you will get all such images and video those are copy right free and you can re use the same>