O genki desu kawatashiwa o genki desuanata wadaijubo desu ka?

O genki desu ka→How are you?

watashiwa o genki desu is wrong. When you describe yourself,do not use [o].

watashi WA genki desu→I'm fine.

anata wadaijoubo desuka? is wrong.daijoubo is daijoubu.

anata WA daijoubu desuka?→Are you well?