Hello Vaishali
You are deploying an war file which is exploding into an folder or directly deploying an folder, and about the webapp folder hierarchy make sure it follows the
Tomcat installation directory/webapps/your web folder/ *.html+*.jsp+web-inf folder/web.xml+[in a folder]/*.class
and web.xml should have an welcome-file list tag with index.html which will be the default one, so
you should have index.html in your web folder
thanks