CN Codes (Combined Nomenclature) are the EU version of HS Codes (Harmonised System) used for international trade. CN Codes usually consist of 8 digits. The first 6 digits are identical to the HS Code.
All goods that fall under CBAM are specified by the European Union in the Annex I of CBAM Implementation Regulation. To identify if your products fall under CBAM, you can compare the CN Codes of your products against the list of goods given in this Annex I.