Sorry if I have misunderstood - I used Google Translate to understand your question.
If you are planning on using a CSV import to add these contacts to the HubSpot CRM, you can create a list of contacts from the import which could be "IT event in the spring of 2023" or you can use a custom property within your CRM which could be orginiated from and have this as a dropdown option.
Another option is to make sure your import is named correctly so you can filter these contacts from the name of the import.