Moving from Drupal to Squarespace

Hi everyone. I have a site made with Drupal and am wanting to switch to Squarespace. I'm leaning towards just building a new site from scratch on Squarespace then just transferring the domain name over, or would it be better to just transfer the entire site over? If I build from scratch, how do I do so whilst keeping the current Drupal website active, then just switch domain names when the new site is done? Thanks strangers!