Hey Kookie!! Copyright is a tricky thing to navigate. If you really don't understand how copyright works, and are using other people's content.. you really need to do yourself a favor and really learn a lot about it. There are tons of videos about it, and lots of ways to research it yourself. You should know that using ANY type of material that is not yours is subject to a copyright strike.. which can lead to termination of your account, and if the person you are "borrowing" their content wants to pursue legal venues, they can.
Once you understand all the ramifications of copyright.. you will want to research "Fair Use". This is when you use copyrighted materials for the whole purpose transforming, education, critiquing, and very selective other purposes. You MAY be able to use it, but even then, that still doesn't mean you cannot be subjected to a copyright action or takedown notification and/or strike on your account. Master how to use apply fair use to the way you want to use this content, and you'll be golden.
Good luck!