Within a month or two, Valve will publish Half-Life: Alyx. This VR game is the first new Half-Life title in 12 years. It's an Alyx-centered prequel set years before the events in Half-Life 2.
To refresh your memory, Valve is temporarily offering all Half-Life games for free via it's Steam platform. You can check it out over here. You'll have to be quick though as this is basically a free trial that expires within two months. There are Windows, Linux, and macOS versions.