Blog migration

<%- if @topic_view.topic.tags.present? %>
<%= t 'js.tagging.tags' %>: <%- @topic_view.topic.tags.each do |t| %> <%= t %> <%- end %>
<% end %>

ss version 4.7

Hi everyone,

I want to use two themes in my website one for blogs and other one for website with two different page.ss files. how can I achieve this in silverstripe 4.

Thanks in advance.