dropdown menus not working

Did you upload both the parent page (containing the Bootstrap CSS and scripts) along with the nav.shtml to your remote server to test?

What is the URL of your test page?

Also validate to ensure there are no critical errors in the combined code.

https://validator.w3.org/

This is the bootstrap code with my image, the Home button and my dropdowns. Is there something wrong with it.  I deleted bootstrap.css and then downloaded a new copy but that did not work. 

<nav class="navbar fixed-top navbar-expand-lg navbar-light bg-light">
<a href="index.shtml" title="The Center for Family Development" class="navbar-brand navbar-brand-font">
<img src="images/logonavbar.png" width="496" height="146" alt="Logo"/></a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent1" aria-controls="navbarSupportedContent1" aria-expanded="false" aria-label="Toggle navigation"> <span class="navbar-toggler-icon"></span> </button>

<div class="collapse navbar-collapse navbar-font" id="navbarSupportedContent1">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="index.shtml">Home <span class="sr-only">(current)</span></a> </li>

<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" id="navbarDropdown1" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> About </a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown1">
<a class="dropdown-item" href="staff.shtml">Staff</a>
<a class="dropdown-item" href="offices.shtml">Offices</a>
<a class="dropdown-item" href="testimonials.shtml">Testimonials</a> </div>
</li>
<li class="nav-item dropdown"> <a class="nav-link dropdown-toggle" id="navbarDropdown2" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Treament</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown1">
<a class="dropdown-item" href="treatmentoptions.shtml">Treatment Options</a>
<a class="dropdown-item" href="dyadicdevelopmentalpsychotherapy.shtml">DDP</a>
<a class="dropdown-item" href="treatmentresearch.shtml">Research</a>
<a class="dropdown-item" href="treatmentchildren.shtml">Children</a>
<a class="dropdown-item" href="treatmentadults.shtml">Adults</a>
<a class="dropdown-item" href="treatmentforms.shtml">Forms</a>
<a class="dropdown-item" href="treatmentarticals.shtml">Articles</a>
</div>
</li>

<li class="nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown3" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Training </a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown1">
<a class="dropdown-item" href="trainingoptions.shtml">Training Options</a>
<a class="dropdown-item" href=""masterclasses.shtml>Master Classes</a>
<a class="dropdown-item" href="certifications.shtml">Certifications</a></div>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown4" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Research</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown1">
<a class="dropdown-item" href="#">DDP</a>
</div>
</li>
<li class="nav-item dropdown"><a class="nav-link dropdown-toggle" href="#" id="navbarDropdown5" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Resources</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown1"> <a class="dropdown-item" href="#">Therapists</a> <a class="dropdown-item" href="#">Parents</a> <a class="dropdown-item" href="#">Articles</a> <a class="dropdown-item" href="#">Something else here</a> <a class="dropdown-item" href="#">Something else here</a> </div>
</li>
<li class="nav-item"> <a class="nav-link" href="booksanddvds.shtml">Books and DVDs<span class="sr-only"></span></a></li>
</ul>
<div class="social">
<a href="https://www.facebook.com/Center-For-Family-Development-181177051901298/"alt="Facebook Icon"><img src="images/facebooksmall.png" class="img-fluid" alt="Facebook Account"></a></div>
</div>
</nav>