Best way to get hundreds of files into Open AI Files section?

Hi,

I want to populate my Open AI account Files section with several hundred PDF files. I’m looking for the best way to do this.

Currently, I can see that if I create an assistant, add 20 files to it, and then delete the assistant, the files still remain saved in the Files section.

If do this over and over, are there any drawbacks? For example, because these files are no longer associated with an Assistant, will they get removed eventually?

Or do I have to create an assistant, add 20 files, then create another assistant, add 20 files, etc.? This would of course just clutter my Assistants section.

Thanks in advance.