In the last few comments you've learned what took me nearly a year ;)
You're doing great!
Not only do you have an account on dtube, but one on every steem interface. There's bunches and bunches of them, and they all interact with the same blockchain with the same login. As you learn about crypro, you'll hear the term "block explorer." Each steem interface is a block explorer on the Steem blockchain. Partiko, steempeak, busy, steepshot, appics, they all have different features and different uses.