How to extend an existing plugin view?

I am using the Rainlab User plugin module, how do I extend the view part? My first question is, I want to add one more field to the preview scoreboard where I will insert data. My second issue is, with the following code, I can remove the avatar field from the user plugin, but the sidebar still remains. Do I need to remove it with CSS or is there a code for it?

.flex-shrink-0.form-sidebar.control-scrollpanel {
    display: none;

To extend the view of a controller;

public function boot() {
public function extendRainlabUserController() {

        \Rainlab\User\Controllers\Users::extend(function($controller) {

            if (!$controller instanceof \Rainlab\User\Controllers\Users) {

            list($author, $plugin) = explode('\\', strtolower(get_class()));
            $partialsPath = sprintf('$/%s/%s/partials/users', $author, $plugin);

And you can copy the _preview_scoreboard.htm into your custom folder (author/plugin/partials/users/{here}) and modify it as you want.

For the second question, it’s related to the first one I think. Take a look into the original view files and see if you can remove what you don’t want ? Ex:

 <?php Block::put('form-sidebar') ?>
        <div class="hide-tabs"><?= $this->formRenderSecondaryTabs() ?></div>
  <?php Block::endPut() ?>

thank you very much it worked