When trying to figure out how to do something the core does programmatically, a good place to start is the core itself. In particular, you want to look at Craft's controllers which handle all interactions with the UI and Craft's services which provide a lot of methods for common tasks.
In this case, you're looking for craft\controllers\SectionsController::...
Class 'modules\importGeoJson\BaseJob' not found
You're getting this error because you're trying to extend the craft\queue\BaseJob, but you're not importing (aliasing) that class. In general, a simple class identifier will be assumed to belong to the current namespace. So since your class is namespaced to modules\jobs, the BaseJob class identifier resolves ...
For anyone strugglng with this. I split the process into a service and a job.
It seems you also have to register your job/services classes in main plugin file first:
'Importgeojson' => Importgeojson::class, // job
'MapitapiService' => MapitapiService::class // service
then call the service ...