Prepend the home page to your page collection, then ignore it.
{{ $p := where site.RegularPages "Type" "post" }}
{{ $p = slice site.Home | append $p }}
{{ range (.Paginate $p).Pages }}
{{ if not .IsHome }}
<h2><a href="{{ .RelPermalink }}">{{ .Title }}</a></h2>
{{ end }}
{{ end }}
{{ template "_internal/pagination.html" . }}