Open the robots.txt file and add / change as per followings rules.
Block your entire website
User-agent: * Disallow: /
Block directory (with everything inside)
User-agent: * Disallow: /itsiti/images/
Block a page
User-agent: * Disallow: /itsiti_index.html
Block a specific file
User-agent: * Disallow: /*.jpeg$
If you want to enable the blocking for certain user agents, you can put the user agent name instead of * (* is applies to all user agents). You can find the list of user agents from this website, Robotstxt.org.
