I kinda hate to agree with the other suggestions here, but entry level and even dedicated NAS products are pretty expensive for providing something you can very easily DIY for significantly cheaper even with the latest hardware.

Was in a similar boat and just ended up taking an old HP desktop and added some cheap HDDs. I ended up playing around with proper Fedora for some LVM cache tricks and running some other services, but the common suggestion for this is SnapRAID and Nextcloud.