Not exactly. Ei is the dative form of is, ea, and id (he, she, and it). Normally we would translate ei as to him, to her, or to it. This sentence uses Dative for possession, so it could be his, her, or its.
"Ei" means "no" in Finnish, so whenever I hear that word in Latin, I get kind of confused. And the fact that the voice in this recording sounded kind of demeaning, I was convinced his name WASN'T Stephanus. It's kind of funny how the brain works at times lol.
From what I have read, the "ph" in Classical/Restored Latin should be pronounced not as "ff", but like "PI-tuitary". For example, "Stephanus" is "SteP-hanus". Step, hanus. Both the "p" and the "h" are separated. Not that it is accented; rather, just exerted/emphasized.
What's the difference between He is Stephanus and His name is Stephanus - in English you'd generally say he is stephanus, his name is stephanus is an extremely long way round to say the same thing but Duo doesn't accept he is Stephanus as correct??
Yes, I think so, the great thing about Latin is that adjectives (such as 'nice') can be switched to before OR after the noun, same with my, your, her, or him. At least, where I am in the Duolingo course :)