Yes, that's right. Hive & Steem is completely separate blockchain.
The Hive frontends are:
https://peakd.com
https://hive.blog/
https://busy.org
while
Steem frontends are:
https://steemit.com
https://steempeak.com
Everyone is entitled to participate / post on both Hive & Steem. It's ok 😊
Note: Your account name & passwords are exactly the same on both Hive & Steem.