Free plan: Database limits and CSV file

Hello.
I’m creating an application that doesn’t make sense to run without populating the data base - 7000 records. It will take a lot of time - 8-10 months, and it seems unreasonable to me to pay for the plan all this time, since in fact the application will not work fully until the database is completely filled.

As I understand it, the only option is to export the database to a CSV file and work with this file. After the required fields are filled in, I can buy a paid plan and import the already existing database as a CSV file. Right?

If so, then the question is that in addition to the fields I created that I will fill in Excel, the Bubble file automatically creates such fields as: Creation Date, Modification Date, User Created and Unique ID. If I do not fill in these fields, then when importing a CSV file, Bubble itself will fill them in “on the fly”?

And by the way, will the upcoming change in tariffs somehow affect the described process of working with the database? Thank you.