Translation:That secretary likes his profession.
Yes, presuming the secretary is male.
It can be "his", "her", "its", or "their", depending on the subject.
I entered "That secretary likes her profession." to test this, and it accepted it. (The sentence as shown in Esperanto is ambiguous.)
As mentioned in the section notes, occupational nouns such a "sekretario" are non gender specific in their base forms.
I entered "The secretary likes their profession" which is accepted too! I think this best preserves the meaning of the Esperanto sentence which doesn't indicate gender. (Yay for singular 'they')
"Secretary" (almost?) always refers to a human, and in English we don't usually refer to humans older than a baby as "it".