Paste some codes in my Joomla Website

My webmaster have disapeared so I want to find someone here in Freelancer. My website [login to view URL] is based on Joomla, and I want to make 4 things: 1.- Sustitute my Zendesk chat for Zoho Sales IQ Chat, the code provided is this one: <script type="text/javascript"> var $zoho=$zoho || {};$[login to view URL] = $[login to view URL] || {widgetcode:"4fc02ec1bfbc4dbd376c4c55ecdd5338e189d07731e50459a36dbfdd056758f4", values:{},ready:function(){}}; var d=document;s=[login to view URL]("script");s.type="text/javascript";s.id="zsiqscript";s.defer=true; s.src="[login to view URL]";t=[login to view URL]("script")[0];[login to view URL](s,t);[login to view URL]("<div id='zsiqwidget'></div>"); </script> 2.- In the contact page [login to view URL] the contact form is no longer working. I want to add a Zoho Form. Zoho gives me JS Code or Iframe Code, whatever works is ok for me. This is the code: JS Code <script type="text/javascript" src="[login to view URL]" id="ZFScript"></script> IFrame Code <iframe frameborder="0" style="height:500px;width:99%;border:none;" src='[login to view URL]'></iframe> 3.- I have a whatsapp button in the left down corner. In the upper part of my site y have a whats app icon with a number. If you click the number it try to call, what I want is to open a whatsapp chat. I need this proyect finished as soon as possible. Thanks