Nextcloud is a fantastic Software for storing and sharing Files plus PIM- Data. With Nextcloud All In One (AIO) you can even have your own private Hosting of Videocalls plus dozens of Features for Teaming without any other Company beiing involved.

As you do have Docker running as described before, you can easyly install a running Instance of Nextcloud to you PC. Heres the original doc: https://github.com/nextcloud/all-in-one