The Copyright Law stipulates that copyright begins on the date the work is completed. The patterns you design, the poems you create, the photos you take, etc., can all be protected as copyrights. Regardless of whether they are registered or not, you all enjoy copyrights. If it is designed by someone else, they will own the copyright of the work from the time of completion. Copyright includes the right of signature, the right of modification, the right to protect the integrity of the work, the right to authorize use, etc.
If you want to use works designed by others, it depends on the purpose. Not all uses involve copyright infringement, such as for research and study, etc. But if it is used for commercial purposes, such as using it to sell your work, it is copyright infringement.
In short, if it is for commercial purposes, it is best not to use it directly. It is best to negotiate with the other party and obtain their authorization.