The display name of a section or a document will change the name displayed on the generated index.
This can be changed inline by clicking on the name in the section/document row and typing in your desired name. When hovering your mouse over the name it will become underlined in yellow to indicate you can change this.
Alternatively, you can amend section and document display names in the properties. To do this, right-click the section or document and select properties.
You can then use the "Display Name" field to change the name of the section or document.
