manual plugin install

wp-manuall-plugin-install

    $url = wp_nonce_url( self_admin_url( 'update.php?action=install-plugin&plugin=automatic-youtube-gallery' ), 'install-plugin_automatic-youtube-gallery' );


    Below you’ll find a function that generates a plugin install link for WordPress. You can use this in the dashboard. This link acts the same way as the “Install plugin” buttons when searching for plugins within WordPress.

    $url = wp_nonce_url( self_admin_url( 'update.php?action=install-plugin&plugin={plugin_slug}' ), 'install-plugin_{plugin_slug}' );

            ----------------- Second solution -------------------

   $action = 'install-plugin';
        $slug = 'akismet';
        $url = wp_nonce_url(
            add_query_arg(
                array(
                    'action' => $action,
                    'plugin' => $slug
                ),
                admin_url( 'update.php' )
            ),
            $action.'_'.$slug
        );