If it's just for your family, then depending on what you need, you could try OnlyOffice— Either self-hosted, or SAAS. They use MS formats as their first-class native format, IIRC, so compatibility is pretty great.

Nextcloud also advertises an office suite, though I haven't tried it. Nextcloud also apparently integrates with OnlyOffice, though I haven't tried that either— Apparently Nextcloud's own office suite is a rebranding of LibreOffice.

I'd probably go with OnlyOffice, either on its own or integrated into Nextcloud.