How can I own my very personal Cloud Server?

I want to own my very own personal Cloud server where I don't have to use any of third party hardware or services no subscription no chain latter etc the reason I want this type of cloud storage server so I can connect my home Electric lock system and CCTV camera via my own server AS I have heard people talking about Nextcloud, ownCloud, Seafile etc but when I done bit of research I found even with these open source software you have to deal with licencing on some stage as describe in following link > https://www.cloudwards.net/diy-cloud-storage-tools/ can someone please suggest which cloud server software I can use to complete my tasks I intend to use Raspberry Pi 4 with largest TB HDD which can Pi handle on Debian 64 bit operating system