Yes, you can use the same Netflix account to watch US Netflix. Netflix shows you the content library depending upon the location of your IP address.
The content library does not depend upon the account information. Therefore, you don’t need a new account for US Netflix.
Get a VPN and connect to a US server for an American IP address.
Similarly, if you’re wondering how to change the Netflix region, you’ll be happy to know that you don’t have to with a VPN. Instead, just connect to a US server and enjoy.