Me and my friends went into an argument that copyright is haram or not? I showed a answer Ayatollah Sistani gave which said “If it is against the law, it is not permissible to sell them, but you can use them.” So does this mean that we can use Copyright is allowed if used for oneself . Can you please explain this

It means that You may not violate copyright, by copying the book -for example-, but if anyone gives you a copy, you may use it.