Hey there @Dynamic88254 - thanks for posting this topic! Check out our New User Guide when you have a chance - it’s a great resource as you learn your way around Calendly! 

When you ask how to change the “host name” are you asking how to change the name of the user in their profile? If so, that’s simple!

Head to your avatar (top right corner) and click “profile” > edit the “name” field > click “save changes” at the bottom of the page.

Once you have updated your name on your account, that will translate to event types etc. 

I hope this helps!