Removing black dots from li and ul
There you go, this is what I used to fix your problem:
CSS CODE
nav ul { list-style-type: none; }
HTML CODE
<nav>
<ul>
<li><a href="#">Milk</a>
<ul>
<li><a href="#">Goat</a></li>
<li><a href="#">Cow</a></li>
</ul>
</li>
<li><a href="#">Eggs</a>
<ul>
<li><a href="#">Free-range</a></li>
<li><a href="#">Other</a></li>
</ul>
</li>
<li><a href="#">Cheese</a>
<ul>
<li><a href="#">Smelly</a></li>
<li><a href="#">Extra smelly</a></li>
</ul>
</li>
</ul>
</nav>
Relatable post
Those black dots you are referencing to are called bullets.
They are pretty simple to remove, just add this line to your css:
ul {
list-style-type: none;
}