Choose a time, place, and activities that will help both of you to talk openly without interruption.
Time
It is very important that you do not have other meetings or commitments during the conversation, because the conversation may take a long time, and it is very important for your loved one to feel that you can devote as much time to him/her as necessary.
Place
It is much easier to talk when a person is in a familiar environment, e.g., at home, in the car, in the park, etc.
Activity
Sometimes it is easier to talk while doing something together, so suggest watching a movie, cooking a favorite meal, playing a board game or cards, etc.
What to do if the person can only be reached remotely?
If you see a worrying message from someone in a public online space, contact them and try to arrange a video call. You can also talk remotely. The most important thing is that the conversation does not take place in a public forum.