I want to create a dropDown menu <select> and fill it with the keys of the students, and when the user clicks on an option (key/student name)=> I want the grades of that student to be printed on the page
Do you have any other code you can show us? You have created a data structure to store the grades for each student. Where is your code for creating the <select>? Are you going to do this completely in JS or are you going to have the <select> in HTML and then just populate it with JS? I think we need you to give us a little more information on what you are trying to do and also all of the code you have tried so far. It doesn’t have to work, we can help you fix it, but we don’t typically write code for people here, so you need to at least get something started that you can show us.
Do you know how to listen for events in JS? You’ll want to listen for the change event on the select list. You’ll create a handler function that will grab the student’s grade info from the object and put it in the <p>.