Hi Naushad,
There’re couple of options:
1. Use co-author plugins. You should be able to find a few plugins that add authors to the posts.
2. Use a block element – post meta.
– Add a custom field to your post, eg.review-author
: https://www.screencast.com/t/KlPqRzdugD
– Add the custom field as post meta to the block element: https://www.screencast.com/t/cHpGw5qnu7
Then it should show like this on front end: https://www.screencast.com/t/7Bj6y8Uwrwv
Let me know if you need further assistance 🙂