How to create personalized covers in InDesign

You can do this using a data merge). Read about it here: https://helpx.adobe.com/uk/indesign/using/data-merge.html.

You would first need to save your names in a CSV file (make sure to include a column heading e.g. 'Names') . Then create/open your InDesign document. Go to Window>Utilities>Data Merge and click Select Data Source from the panel menu. Choose your CSV file and click Open. Next, place the insertion point in the text frame and position where you would like the name to go. Then, in the Data Merge panel, click the name field; this should add a placeholder. Once done you can preview the data merge by selecting Preview, amend as required then select Create Merged Document from the Data Merge panel menu. Here you can choose to either merge to a new InDesign document or PDF. 

Depends on the layout - and amount of information - and if you have covers as a separate file - you could just create a TextFrame on a Master Spread and flow your text with StartOnNextPage in the ParaStyle options - much less hassle than DataMerge 😉 

Use Data Merge.

Create the book cover template with a field for the name. Merge that with a list of names from almost any source (Word, Excel, a text file, etc.) Voilá.

Start with the Data Merge pane — Window | Utilities | Data Merge, especially its 'hamburger icon' menu. Help and tutorials are easy to find and you can ask here if they're not enough.