Using the Outlook When a New Email Arrives (v3) trigger you can filter for emails you receive based on a subject. That's one way you can get the responses to your email.
To add it to an Excel table you can do this either using the standard ExcelOnline connector actions or using Office Scripts (specifically Office Scripts with Power Automate) (the Run Script action in the ExcelOnline connector).
If using the ExcelOnline connector actions you're going to have to:
1. Get the existing information in the column from the row
2. Append the new information taken from the Outlook trigger to this existing information
3. Write the newly created information from ^ back to the row
If using Office Scripts, you just need to write a script that does the above. If you know javascript this is probably the less finicky option since you can test your script instantly without having to run a Flow. I can also help provide a script that probably works for you here.