Making a dropdown menu

Hey everyone,

So I'm very new to coding and I was wondering if someone couldhelp me make my nav a dropdown menu?

Here's my code:


#menu_wrapper {
clear: both;
width: 100%;
height: 95px;
margin: 0 auto;
}

#menu {
clear: both;
width: cover;
height: 75px;
margin: 0 auto;
background: #3EDAAD;
}

#menu ul {
width: 1000px;
overflow: hidden;
padding: 20px 0 0 0;
margin: 0px auto;
list-style: none;
text-align: center;
}

#menu ul li {
padding: 0px;
margin: 0px;
display: inline;
}

#menu ul li a {
float: left;
display: block;
width: 100px;
padding: 4px 0 5px 20px;
font-size: 18px;
text-align: center;
font-weight: normal;
text-decoration: none;
color: #212629;
outline: none;
}


/* end of menu */



<div id="menu_wrapper">

<div id="menu">

<ul>
<li><a href="#">Home</a></li>
<li><a href="#">Our Project</a></li>
<li><a href="#">Outreach</a></li>
<li><a href="#">Notebook</a></li>
<li><a href="#">Parts</a></li>
<li><a href="#">Team</a></li>
<li><a href="#">Collaborations</a></li>
<li><a href="#l">Interlab Study</a></li>
</ul>

</div> <!-- end of menu -->