nvs add <version>
Downloads and extracts a requested node version. An added node version is then ready to activate with a USE command.
A version string consists of a complete or partial semantic version number or version label ("lts", "latest", "Argon", etc.), optionally preceded by a remote name, optionally followed by a processor architecture or bitness ("x86", "x64", "32", "64"), separated by slashes. When a partial version matches multiple available versions, the latest version is automatically selected. Examples: "node/lts", "4.6.0", "6/x86", "node/6.7/x64". An alias may also be used in place of a version string.
A remote name is one of the keys from the remotes mapping in $NVS_HOME/settings.json; these may be managed using the nvs remote command.