Flow syntax support is no longer enabled in v7. In babel 7, this command has been split out into its own @babel/node package, so if you are using that command, you'll want to add this new dependency. Babel is a toolchain that is mainly used to convert ecmascript 2015+ code into a backwards compatible version of javascript in current and older browsers or environments.
This will be a quick introduction to those tools and you can read more about them in the usage section of the docs. Extending this list isn't possible, however @babel/cli does provide ways to support other. Learn more about babel with our getting started guide or check out some videos on the people and concepts behind it.
Instead, you should use a build system running on node.js, such as webpack, rollup, or parcel, to. This list is used by @babel/register and @babel/cli to determine which files need transpiling. 1compiled output will be shown here Using babel how to use babel with your tool of choice.