We have recently purchased a E Learning Application and wanted to link Community portal so that Portal users can click on particular link which will click Visualforce Tab and redirect to new application. 

Most of code is already in place as i am moving from one application to other. I dont know how to use Visualforce Tab in below visualforce page. 

<p><a href="{!wmURL}" target="_blank" class="btn btn-primary">{!$Label.lbl_vetPortal_WeightManagementLogin} &rarr;</a></p>

!wmURL has a logic in Controller of old application. I want to use Visualforce Tab when user click on above link. 

apex:page docType="html-5.0" showHeader="false" sidebar="false" standardStylesheets="false" applyHtmlTag="false" controller="ctl_PortalWeightManagement" action="{!getUrlForUser}">
    <apex:composition template="vetPortal2015Template">
		<apex:define name="content">
			<div class="row">
				<c:vetPortalLearningCenterNav />			
            	<div class="container col-sm-11">
		            <header class="page-header">
		            	<h1>{!$Label.hdr_VetPortal_WeightManagement}</h1>
		            </header>
					
					<div class="pull-right-img">
						<img class="img-responsive" src="{!URLFOR($Resource.vetPortal2, 'images/cundari/boxer.png')}" />
					</div>
					<p><apex:outputText escape="false" value="{!$Label.txt_vetPortal_WeightManagementContent}" /></p>
					<p><a href="{!wmURL}" target="_blank" class="btn btn-primary">{!$Label.lbl_vetPortal_WeightManagementLogin} &rarr;</a></p> [I am looking for change here as this was used for login to old application]
				</div>
			</div><!-- row -->
        </apex:define>
        <apex:define name="scripts">
			<script type="text/javascript">
				$(function() {
				});
			</script>
        </apex:define>
    </apex:composition>
</apex:page>

Seeking your help here. Thanks in Advance.