What is the ruling on working as a supervisor of a computer center where women are abundant, knowing that he may be alone with one of them in one place when needed to provide her with information about the internet, but he remains outside the room until one of them asks for help?

Everything that leads to the mixing of non-mahram (definition) men and women, as is common now, is forbidden, unless there is a need for a man to be among women to teach them or similar, and no woman is available to do so. In such cases, both parties must adhere to the Shariah guidelines, which include lowering the gaze, refraining from speaking except when necessary for work, and avoiding khalwah (private seclusion). It is not permissible for you to be alone in a place with one of the female employees, even if she is inside the room and you are outside it, because that constitutes khalwah. One should seek work that is free from prohibitions.