Online counseling or online psychotherapy services certainly can help your personal development and provide mental health treatment for your psychological problems.
Since an online counselor or psychotherapist cannot really see you in person, this can prevent their ability to evaluate your difficulties in life. Psychotherapists make use of your body language very often. This is a very valuable data for them.
On the other hand, since our thinking is mainly (in fact completely) based on language, online counseling and psychotherapy has not much lacking in terms of healing your thinking or any possible psychological disorder.
The treatment that online therapy offers can be evaluated mainly as cognitive behavior therapy. A psychoanalytical or a dynamic approach could not be available through online services because they require the presence of the therapst and the client at the same room.
So, you can make a choice, you can differentiate online therapy and therapy in a room in terms of the psychological disorder or uneasiness that you want to work on.
If you are in depression and your depression is related to cognitive distortions then online therapy may be very helpful on that. However, if your depression is rooted in past events, I would doubt that you can work on that online.