I want to have a question "Do you have any questions?" at the end of the instructions and if people click yes, then I would like to see in the admin interface that and who did that. Any hints how to approach this?

Hi Trontatuma,
The easiest that comes to mind is to add a binary input Yes/No to the question so it is stored in the database the moment they finish the instructions.
Then show the values of this variable in a table with all subjects at AdminReports. You can learn how to enable Admin reports at the docs:
https://otree.readthedocs.io/en/latest/admin.html?highlight=admin%20reports#customizing-the-admin-interface-admin-reports
I would also add a waitpage after they finish the instructions so you know when to refresh the AdminReports (they are not live updated like Monitor).

You could also add a page after the instructions that is only displayed for those participants who reply that they still have questions (via is_displayed, see https://otree.readthedocs.io/en/latest/pages.html#is-displayed).

This way, you can immediately see on the “Monitor” page to which participants this applies. Moreover, by giving the page a name like I_STILL_HAVE_QUESTIONS, you can make the entries on the “Monitor” page salient.

Thanks a lot for the suggestions!!!