How to add data to your Lightspeed map at Lucy start-up explains how you can use the configuration files to define which data is loaded when a new map is created.
To specify a WMTS coverage, you can use a String of the following form:
${server_address}?layer=${coverage_name}
For example:
https://sampleservices.luciad.com/wmts?layer=92c09725-a9c5-46fb-bffd-d9e23b4abbf2
See the documentation of the TLcdWMTSDataSource.Builder.uri
method for more information about the structure of the accepted URLs.