Hi @Vaishnav_S ,
You can write a Rewrite rule in AEM dispatcher. Something as mentioned below.
RewriteRule ^/(.*)$ /$1.html [R=301,L]
If you want to handle it within AEM, Apache Sling Resource Resolver Factory can be used.
Please refer below article for more details.
https://blog.3sharecorp.com/shortening-urls-in-aem