Ogenki desu ka? is a set phrase that means "How are you?"
But the literal word by work translation is as follows:
Ogenki: the "o" is an honorary prefix. That makes the word more polite. genki means good health, good energy or something like that.
Desu: desu is like the verb "to be".
Ka: ka in japanese is an indicator that the sentence is a question. it is like a japanese question mark.