Hi @AureliaC,
Instead of the tutorial suggested by Zhenya Kovalyov I would recommend this one assuming the client is interested in price history. AdxRtHistory that the tutorial suggested by Zhenya is about is a legacy object and should be avoided.
https://developers.thomsonreuters.com/eikon-apis/com-apis-use-microsoft-office/learning?content=3563&type=learning_material_item
If the client is interested in other types of history such as dividend history, earnings history and so on and so forth, I recommend the user to look at the following tutorial:
https://developers.thomsonreuters.com/eikon-apis/com-apis-use-microsoft-office/learning?content=5760&type=learning_material_item
have a look at this tutorial
https://developers.thomsonreuters.com/eikon-apis/com-apis-use-microsoft-office/learning?content=3558&type=learning_material_item