Dear Bhatt,
Thanks for your updates.
I'm glad to hear that it works in your environment.
You can change the part 'From': '******@sharepoint.com' to 'From': '******@contoso.onmicrosoft.com' to make the email sent from the user. However, the ******@sharepoint.com part will be showed in the generated email as well. This may be unable to be changed. For the following example, the flow can make the email sent from Adele Vance but ******@sharepoint.com is showed in the email.
Thanks for your understanding.
Cliff