Can I apply a demo design to my site/page, with MY content, not dummy content?

If i import a new demo for woodmart, can I apply it to work with my own content instead of demo content? Ideally i would try to do it withi just one page, say with a copy of the home page, and then if it works well, i want to apply it. but if i import it, all demo content will show up (i.e. instead of my existing blogs text, demo text will appear). Am i doing this correctly? or is there a better way for an existing site to keep the same content but with new demo’s design and layout? Please let me know how to do that, thanks!