Import several different texts

As already addressed, if you are talking about a merge or 'assembly' in a few steps, data merge may meet your needs.

If you are simply asking if an InDesign document can have multiple text flows, yes. Most documents have one long connected text flow that adds as many pages and text frames as needed. The other document model is to add pages and put a separate text frame on each page, then paste or Place text within it. ID has tools to manage multiple "stories" in this manner if individual management is not adequate.

Maybe you mean something like Data Merge (add all the pupil data in an Excel Sheet and then automatically insert this data in InDesign)?

You can find some more information on this page:

https://helpx.adobe.com/indesign/using/data-merge.html

If this is not what you're searching for, can you provide us with more information about what you want to do?