Hi @laz8592 ,
Actually your current flow looks great and almost achieve the intended results, so let's just make some small changes on it 🙂
I see that your current flow is capturing your own user data (email and display name, extracted from 'Get my profile' action ) to populate the email template. If I understood correctly, you want to keep this same process (when a record is added to the list, send the email to user 'x'), but just replacing yourself for this user 'x', right?
If this is the case, you can achieve it by just replacing the 'Get my profile' action for a 'Get user profile (V2)' action, using the user 'x' email address as input:

After that, you will just need to add the dynamic content to your email template again.
To include this user into the 'Update item' action, add an 'Update item' action, set the 'Id' with the dynamic content of the 'ID' from your trigger (highlighted in yellow), and set the 'Assigned to' with the 'Mail' dynamic content from the 'Get user profile' action (highlighted in green).

Based on the flow design that you shared, it looks like you are comfortable with dynamic contents, but if you find any trouble with it, check this article that I recently wrote about how to use it: http://digitalmill.net/2023/07/31/using-dynamic-content-in-power-automate/
If the steps below are not clear or it does not exactly solves your problem, I will be happy in provide you with more details or in investigate new solutions.
Let me know if it works for you or if you need any additional help!
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