Convert Paper UI knx setup to GUI version

Recently I have migrated my setup from openhab 2 to openhab 3. In the end everything was working as before. Now I am at the next phase and want to convert my paper set-up to the GUI version of OH3.
I have found the option to import thing from the paper UI, but not found this for the channels.
Do I manually need to create all the channels one by one and link the corresponding items to it? Or have I overlooked the a possibility to generate the channels as well.

There is no import for Things but only for items :wink:
But of course it’s possible to export all Information in openHAB through REST API and import it in openHAB3 the same way.