We ask that you use your real name for your texting profile, as well as a valid email address.
However, we know that there are times you may wish to change your first name - for instance, if you are texting voters and your name appears, you may wish to change your to a gender-neutral name in order to eliminate unwanted "romantic" responses. You can always update the first name that appears in your profile as you are texting based on what is best for you.
Contacts are unlikely to see your last names unless your Workspace has decided to include it in their messaging for some reason. If you have questions about this, please contact your Workspace's texting lead.
See more here: What Personal Info will contacts see when you text them?