That is just the default as it is guaranteed to work which may not be the case with the main domain. For example if the domain name was pointing elsewhere or not registered. However they would be able to access the normal without redirecting.
They can go straight to:
https://domain.com/wp-admin/install.php
You can also do this:
1. Just delete all files and folder fo the domain file manager- https://cp.hostverge.com/services/65054025fb6b64b7/file-manager
2. Now use 1 click install and install wordpress
3. After, you will see both main URL and Temp URL: https://jaydeepharia.com/
4. Just add this /wp-admin/install.php after website main URL: https://jaydeepharia.com/wp-admin/install.php