Get User Name on Form

You can add a field onto your form that takes in the users email by default. Make sure not to display the field, and have the default value be the current users userid or their email address.
{% CurrentUser.Email |(identity)GlobalAdministrator%}, if using the userid, you will have to fetch the email through a macro, but that will make it a bit more flexible, and also account for when users change their email, may or may not come into play or be necessary. Email will be easier to work with, so if not comfortable with macros, I would suggest sticking with that for now.

Then in your email, reference the new field, just like the other fields.

Thank you! That got the information I needed; however, when I add {% CurrentUser.UserID |(identity)GlobalAdministrator%}. Do you know why this is happening?

Thats a security parameter that kentico uses. It shouldn't stop the macro from resolving. By default, it "signs" the macro for security. Is your macro not resolving?

I see what I did, I didn't click the > before entering the value. Thanks!