There are several websites that offer copyright-free videos that you can use to upload on YouTube. Here are a few options:
1. Pixabay:
Pixabay offers a large collection of copyright-free videos that you can use for any purpose, including commercial use.
2. Pexels:
Pexels also has a large collection of copyright-free videos that you can use for free, even for commercial projects.
3. Videezy:
Videezy provides free stock footage and motion graphics that are free for personal and commercial use.
4. Videvo:
Videvo offers a wide variety of free stock footage and motion graphics for personal and commercial use.
5. Coverr:
Coverr provides free stock footage and motion graphics that are free for commercial use.
It's important to read and understand the license agreements on each website before using any video to ensure that you're following the rules and not violating any copyright laws.