A user who has permission to edit & delete a key result will see 'edit' & 'delete' actions on objective detail as well as in list and thumbnail view on browse OKR page. Images below show how can you edit or delete KRs from each view.
Objective detail page
Edit & delete options available in actions of each specific KR section.
Edit & delete options available on mouseover on KR.
Jira issue that is added as a key result or Jira issue added as a key result via JQL can only be removed as a key result, there is no edit action possible on Jira issue from UpRaise.