Дмитрий

RewriteEngine on

RewriteCond %{THE_REQUEST} " /projekts/([^/]+)/page\.html" 
RewriteRule ^  https://site.co.ua/%1 [R=301,L]

RewriteCond %{DOCUMENT_ROOT}/projekts/$1/page.html -f
RewriteRule ^([^/]+)$  /projekts/$1/page.html [L]