Thanks for the question. If it's only a 100 emails, you can divide it between two emails (50 recipients per email is max). You can always utilize a mailing list program such as phpList or go to a third party and use mailchimp.
If you intend to send bulk mail (especilly from a budiness account), then you would need to submit a bulk mail request.
I hope this helps to answer your question! Please let us know if you have any further questions or comments, please let us know!
Sorry, my question was unclear. I have 100 email accounts to set up.
Can I set them up from a file?
Thanks for clearing up the question. The good news is that yes you can bulk setup 100 email accounts, but they would need to be in a CSV format and then you would need to run an import. Here's a tutorial that explains it: