There’s no straightforward answer to this question. Some movies are legal to download whereas others are not. It could also depend on where you live. If files are not copyright protected it is not illegal to download and use them. Uploading your own home videos to share, or watching someone else’s they invited you to watch is perfectly legal. Streaming or downloading a copyrighted movie is legal if it’s only being used for personal viewing. Sharing the download online or in any other way is illegal. If a movie has been pirated, it is definitely illegal to download it and then to share it. It is illegal for any sites to upload it to begin with.