how is the way to put a username as a variable for a custom template as a subscription?

Hi, I develop a custom template, but my template need show the name of the user, for example:

I want the name change for each user that receive the email. But the problem is... that I don't know how tell that to my template (in code). Is there any a block of code, variable or class for that?

Like:

Hi,{ $usernameFromList }

Or

Hi, <span class="somethingMarketo">$usernameFromList</span>

I hope you have made me understand.

Thank you.