DITA elements in AEM Guides are mapped to their corresponding AEM components. The mapping is defined in the elementmapping.xml file, which can be accessed
from the CRXDE Lite mode at this location - /libs/fmdita/config/elementmapping.xml
You should overlay this file to your project folder under /apps and define the mapping for your text component.
More details are available in this documentation under "Customize DITA element mapping with AEM components" section.
Links can be added using xrefs in your dita file with the scope attribute set to external and published to sites.