All therapists are licensed with their applicable licensing board after successfully completing the necessary education, exams, training, and practice. This means that when you talk to a licensed therapist online, they are subject to the mandated reporting and confidentiality requirements of their governing board and respective state laws, similar to in-office therapy.
Generally, the therapist will keep what you tell them confidential, but there are limited exceptions. For example, if you threaten grave harm to yourself or to an identifiable victim the therapist is required to report this information to relevant authorities. Before starting therapy, please discuss with your therapist their legal obligations to confidentiality if you have any concerns or questions.