Are all of your family playing on Bedrock edition? There is a version split between console editions (plus some Windows users) and the original Java edition, with most of the (verbal?) online community playing on the latter.

If you are not all playing on the same edition, you can use something called GeyserMC (https://geysermc.org/) to allow Bedrock players to join your Java server.

Modding your server can greatly improve your server performance. Java is the platform with the best modding support. The modding APIs are however community built, due to historical and upsteram reasons. The subjectively best API for development (in my opinion) is Fabric (https://fabricmc.net/), but many older mods have only targetted Forge. Due to a split in the Forge development team, this API was recently superceded by NeoForge (https://neoforged.net/). Most relevant mods support both Fabric and NeoForge.

To explore mods, I would recommend using Modrinth. It has a pleasant and powerful interface, and links to source code on open source mods.

https://modrinth.com/

Here is a search filter for an overview of server-side optimisation mods:

https://modrinth.com/discover/mods?g=categories:fabric&l=ope...

To set up your Minecraft server, I would recommend NixOS (https://nixos.org) for devops with nix-minecraft for server configuration:

https://github.com/Infinidoge/nix-minecraft

Feel free to ask clarifying questions if you have any, I might have written this somewhat compactly!