Maybe like this

themes/learn2-dark/templates/partials/sidebar.html.twig

@@ -10,10 +10,10 @@
         {% set parent_page = p.activeChild ? ' parent' : '' %}
         {% set current_page = p.active ? ' active' : '' %}
         <li class="dd-item{{ parent_page }}{{ current_page }}" data-nav-id="{{ p.route }}">
-            {#<a href="{{ p.url }}" {% if p.header.class %}class="{{ p.header.class }}"{% endif %}>#}
+            <a href="{{ p.url }}" {% if p.header.class %}class="{{ p.header.class }}"{% endif %}>
                 {#<i class="fa fa-check read-icon"></i>#}
                 {#<span><b>{% if data_level == 0 %}{{ loop.index }}. {% endif %}</b>{{ p.menu }}</span>#}
-            {#</a>#}
+            </a>
             {% if p.children.count > 0 %}
             <ul>
                 {{ self.loop(p, parent_loop|default(0)+loop.index) }}