How to add plonetheme.barceloneta to plone 6 Classic?

I am new to Plone 6, so maybe it's a dumb question.

I follow the doc over the net to install Plone 6 and after that I got a broken site, no theme / css etc.

How can I add plonetheme.barceloneta?

I used to be using buildout for plone install. So I have no idea. Can someone point my out.

Many thanks.

I place a dumb question as well, did you create the site clicking the "Create Classic Plone site" button?
image

Perhaps you are on 127.0.0.1, thats per default unstyled. You can disable this "no-style mode" in the configuration panel. configuration -> design -> Remove the host entry under "hostname without design"

Thanks for all reply I have find the way to do it