Attaching a domain to a new site, how to understand it correctly?

Question

Search Engine Optimization

Tell me if the site (domain) is promoted/optimized by Yandex/Google, etc. , when creating a new site and attaching this domain to it, the site will also be optimized (promoted) like the old one? In other words, when promoting an online store in search engines, do we promote only the domain or the domain and the site itself?

Answer 1

Not the same, but it gives a boost, the main thing is that the new site and the old one have the same theme.