thanks in advance
@Douglas McPhaden By DM, we assume you mean Direct Message? If not, please explain.
You can send a private (direct) message to another user of FamilySearch Community, depending on how the person set up their Community profile. If you want to send a private message, click the person's name in a post and then click Message. If the person has set their profile to be private, you will find you are not able to send a message to them.
After you send a message, the other user sees a dot in the top-right on the envelope icon and possibly on the bell icon to alert them to a private message. Again, it is going to depend on their profile settings,. If they choose, they can reply to you directly. Here is a Help Center article that explains the how-tos.