I don't understand by something add but I believe you want to show some content on only question page (Question View) if that is the case than use below code.
Wrap your code with the condition below
if ( $this->template === 'question')
//put yoru code for something here
EDIT: With more detail
In your theme file qa-theme/your-theme-dir/qa-theme.php cross check if there is sidepanel() function already placed. Add/Update the code below
if ( $this->template === 'question' )
//add your code here
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