The next step for you is to copy the Lightning address you created in Alby and add it into your profile in the field that says Lightning address or Lightning tips. Once you do that we will see it and can #zap you. And Alby also lets you send zaps as well.

It’s called a custodial wallet because it’s managed by a third party. After you have had some time to explore how it works, you should look into using non-custodial wallets as well. Again, feel free to #AskNostr if you get stuck on anything!