So what's happening if you try to access to your domain adding 8080? (I mean www.domain.com:8080)
Did you configured Varnish to run on port 80?
Also, you'll need Nexcess_Turpentine module for Magento1 (Magento2 has native support vor Varnish).
If you want to add Varnish to M1 isn't something that you just install and start to use. You'll need to apply some tweaks probably.