For Mapping The Categories and Attributes,

• Go to your OpenCart admin panel.
• Place cursor on sign. When the menu appears, click Categories, and then Category and Attribute Mapping.

• You will be navigated to the page as shown below:

• Click on the ‘+’ (Add New Mapping) button highlighted on the top of the page in the above image.
• On clicking it, you will see the page as:

• In Cdiscount Category, enter the Cdiscount category with which you want your OpenCart product category to be mapped.
• In Store Category, enter your OpenCart category with which you want the Cdiscount category to be mapped. You may select more than one OpenCart category in this field.

• In Attributes Mapping, the required Cdiscount attributes need to be mapped with OpenCart product attributes.
• In the fields under Mapped With, select the required attributes to be mapped with the Cdiscount attributes.
• Once categories and all the attributes have been mapped, click on Save button on the top of the page as shown below:

• The category and attribute mapping will be done successfully.