Redirect site old.site.com and all subfolders (e.g. old.site.com/subfolder) to new.com.
RewriteEngine on
RewriteCond %{HTTP_HOST} !^www\.old\.site\.ee$ [NC]
RewriteRule .* https://new.com [R=301,L]
NB! If subfolder old.site.com/myfolder does not exist, then it redirects to new.com/myfolder, otherwise it redirects to new.com.
Read more:
https://help.zone.eu/kb/301-suunamine-htaccessiga/
https://help.zone.eu/kb/naiteid-htaccess-faili-rewrite-reeglitest/#h2strongkoikide-paringute-suunamine-uhe-domeeni-pealestrongh2