I would like to create a web site with many images. But I would like to protect against direct access to images, e.g. direct links to images without visiting the web site.>
Add Deny Rule in your .htaccess
RewriteEngine on RewriteCond %{HTTP_REFERER} !^http://(www\.)?domain\.ltd [NC] RewriteCond %{HTTP_REFERER} !^http://(www\.)?domain\.ltd.*$ [NC] RewriteRule \.(gif|jpg|js|txt)$ /messageforcurious [L]