I searched a lot, but nothing worked. There are downloadable Makros who manage to add labels you type into them, but as they´re not open source I can´t get behind that magic, which of course works, as I tested. Using the REST Api didn´t work, using the labelManager and labelUtil also lead to nothing. But I am sure there´s a way to use the labelManager to do so, maybe with the function "<strong><a href="https://docs.atlassian.com/confluence/latest/com/atlassian/confluence/labels/LabelManager.html#addLabel%28com.atlassian.confluence.labels.Labelable,%20com.atlassian.confluence.labels.Label%29" rel="nofollow noopener noreferrer">addLabel</a></strong>(<a href="https://docs.atlassian.com/confluence/latest/com/atlassian/confluence/labels/Labelable.html" title="interface in com.atlassian.confluence.labels" rel="nofollow noopener noreferrer">Labelable</a> content,
<a href="https://docs.atlassian.com/confluence/latest/com/atlassian/confluence/labels/Label.html" title="class in com.atlassian.confluence.labels" rel="nofollow noopener noreferrer">Label</a> label)" but there I don´t know with what to fill the parameters, beacause I have no access to the current page and I don´t know how to create a new label.
Thanks for your help