Generally speaking, planning the topic (writing a book topic planning)-contacting the author to make a draft-reviewing the manuscript (if it is unqualified, it needs to be revised or rejected by the reporter)-designing and typesetting (there are specialized personnel, but the editor should explain the specific requirements)-proofreading (in fact, it should not be the job of the editor, but now the publishing unit is all editing and proofreading in order to save money, strictly speaking, it needs three proofreading-printing and typesetting.
The editor's main task is to ensure that the published content is excellent and accurate, but he should also participate in the whole process of book publishing. It depends on what kind of enterprise you are. If you are a small private book company, some book editors need to collect materials themselves to assemble manuscripts. Large publishing houses pay more attention to planning. It is important to make friends in the author's circle. Editors' income is linked to book sales.