How do you define a professional email address? Easy. One that has your name and/or website domain.
I like to think that there is more to it than just that. Your email should also be really easy to remember and spell if possible. If it's not then people will just give up if they spell it wrong and they won't end up contacting you.
So two main things: must have at least a potion of your name to be recognizeable and must be easy to spell and short enough to remember.
For instance: if I had an email that was firstname.lastname@example.org, I might consider changing it to something more professional. How about Martin.Bentsen@gmail.com? That could work, but what if people don't know how to spell my last name? I might want it shorter and easier. What about Martin.email@example.com? That might be taken. What about Martin.firstname.lastname@example.org? That could be too long for memorization, and might not be recognizable.
What about m.Bentsen@gmail.com? That could work. Since my name is hard to remember but Martin.b is already taken, I will use this. At least it's recognizable, and if I have a card it will be easier for people to spell my last name correctly.
Use a professional email address, whoever you are!
Hey I'm Martin, and my goal is to help you reach yours. I love writing content about career advancement, marketing strategies, productivity, and much more.