How to add a CTA (Call to Action) Button to your secondary menu + code

How to add a CTA (Call to Action) Button to your secondary menu + code


And this is the code:

.ctabutton a{
background-color: #4CAF50;
border: none;
color: white !important;
padding: 15px 15px;
text-align: center;
text-decoration: none;
display: inline-block;
font-size: 16px;

}
.ctabutton {border: 1px solid #ffffff;}
.ctabutton {
margin-bottom: 10px;
}

#et-info{
padding-top: 16px;
padding-bottom: 8px;
}