There are several ways you can do this.
If it’s just a few items of data, then you could just create a microflow to create the entities and set the fixed values.
If you have more data, have a look at something like the CSV or Excel Importer modules which can used to import a large amount of comma separated values. You could also read in XML or JSON files using a standard import mapping.
In most of my projects we usually have an After Startup microflow that checks if the expected data is present, and if not call the import routine to setup the initial values. This also means anyone joining the project has it in a good working state from their first run.