Can't set up a redirect on a wordpress site?

Question

Domain name market

Good afternoon.
A friend of mine has a WordPress site for a long time. He did it himself, and out of inexperience messed up. Now his site has an address like www.sitename.ru/wordpress
Now he asks me to help with this.
In this regard, the question is: what can be done so that the site address takes the normal form of the www.sitename.ru type and at the same time pages and records that already have some indicators with search engines (and there are links to them on the network), did not lose their weight.
I tried to achieve what I want by adding

RewriteRule ^wordpress/(.+)$ http://www.sitename.ru/$1 [R=301,L]

to the .htaccess file
But either because there are two such files (one in the root of the site, the second in the same wordpress folder), or for some other reason, but it didn’t work.
Help.
Thanks in advance.

Answer 1

You can start here:
codex.wordpress.org/Giving_WordPress_Its_Own_Directory