Q: In the server domain; Do I use the smtp server OR the incoming mail server?

I am trying to verify my business mail on my iphone and I have several troubles thus I would like to ask for you help:

1) its a "webmail.ath.hcmr.gr" mail, so it is a "Microsoft Exchange" mail type? Correct?

2) in the server field: what do i add? The incoming mail server or the smtp server?

Thanks