education

I graduated from The Russian Orthodox University. I have acquired a profession of ecologist.

[OK, better is <em>I have become a professional ecologist]</em>

It's (meaning <em>it is) </em>usual a regular/normal university where you study natural science subjects, but also you study subjects about Orthodox religion.

Nice and clear.  "Usual" is a difficult word to get right.  With a noun, regular/normal/ordinary would be recommended as it they have fewer problems.