How to make a mirror of your site for Yandex.Webmaster and Google.Webmaster?

Question

Search Engine Optimization

Good afternoon, dear toasters!
Faced with the problem of misunderstanding what to do next.
There are 2 domains in the property: www.sleepbaby.su and www.sloniki.su, currently registered on a free hosting.
www.sloniki.su is an old site that is currently empty, all site files have been deleted, and a redirect to www.sleepbaby.su has been made through the hosting control panel.
www.sleepbaby.su is an active site that is being filled with content. This site is included in Yandex.Webmaster and Google.Webmaster and is being indexed (if I'm not mistaken with the term).
As far as I know, you need to indicate the old site as a mirror of the new one, so that Yandex and Google understand this. But here's the problem, I don't understand where and what information needs to be entered. did "Ok, Google", but on the sites read everything is written in terminology and, accordingly, an inexperienced person does not quite understand further actions.
Dear experts, if anyone can describe in simple terms, sequentially what actions need to be performed.
Thank you all in advance for any help.

Answer 1

As a rule, it is enough to set up a redirect on the old domain. The search engine will figure it out.