You can create multiple users on your server and share your albums or individual assets with them. You can also create public sharing links that anyone can access, just like Google photos. You'll of course need to make the server accessible to them in some way.

My server is hosted at home in a Raspberry Pi and an SSD for storage. I have a public domain name and it is forwarded to my home network through CloudFlare. Might be a little risky security-wise, but I want to eventually make this instance usable for my parents.