while creating my custom theme i am getting a error "This theme is missing a 'content' region.".please have a look on screen attached(designed by manoj kumar).any help would be appricated.
Looks like you need to indent your region names 2 spaces. See https://www.drupal.org/node/2349827 for more information on defining a theme with an .info.yml file.
Also the link in your description is missing a closing tag.
You should also be quoting some of your strings. There is a link on the page above to read the quick introduction to the YAML file format that takes you to http://symfony.com/doc/current/components/yaml/yaml_format.html . That page provides good information on quoting strings.