Can somebody help me to create a drop-down menu or (radio buttons) in WordPress comment form, so that a new user could make a selection of their user roles (for example teachers + students) ?

1. Output from dropdown list or radio button would appear somewhere in
   the comments area.
2. The best of all would also be if WordPress which already automatically populate
   email, login name would also display new extra field info (dropdown list OR
   radio button) to logged in users who already has their user roles
   assigned
3. I don’t want to use a plugin for that.
4. I know that there a lot of tutorials about adding extra custom
   fields to the comment form including this web where I have found 3
   similar requests unfortunately marked as duplicates, on my opinion
   they are not dups at all, because there’s no code or tutorial for
   using known values as (select – dropdown- radio) button.