How to remove "Drupal" from title of page?
Drupal by default will put the site name at the end of the page title but specific themes might change this.

if you want to override this your best bet is to use https://www.drupal.org/project/metatag module and override appropriate settings 

There is a setting for first page or for all content types or specific content types; it very configurable.

Or you might do it programmatically in your THEMENAME.theme file:

function THEMENAME_preprocess_html(&amp;$variables) {       
    $variables['head_title']['name'] = "Another Name";
}


To take away the | you have to create a new html.html.twig template in your custom theme and modify (copy paste it from the theme you are overriding)

    &lt;title&gt;{{ head_title|safe_join(' | ') }}&lt;/title&gt;


to something like this 

    &lt;title&gt;{{ head_title|safe_join('  ') }}&lt;/title&gt;