Need some help with JS.

I need your help regarding JS. On my website (https://quick*****ing.ie/courses/community/add), you will notice that there is a field called “Course Categories”. I have used JS similarly to auto-populate the selection from the title drop down to this field but the only text gets written and no category is actually selected. I mean the title user select category will be selected based on that. https://monosnap.com/file/kd9XUopErGN3MNwTzkOvu40p0Yi7Xx

Please help with the JS need for that.

Another issue is One this page: https://quick*****ing.ie/courses/community/add

You will notice a dark grey button saying “New Ticket” under the “Tickets” heading. If you click on it, you will see two different fields.

I want to hide the New Ticket button and show the two fields by default. I tried using JS to click() function for that button but it works and show the field but field value doesn’t get saved then. If you can help on this also that would be great.