Login as an administrator, Click on site setting > Click on Go to Site Administration >Click on Manage anonymous access > Choose one of the three conditions on what Anonymous users can access
Login as an administrator, Click on site setting > Click on View all Site contents >Click on Manage anonymous access > Choose one of the three conditions on what Anonymous users can access
Login as an administrator, Click on site setting > Click on Go to Site Administration >Security > Choose one of the three conditions on what Anonymous users can access