Geyser VS GeyserConnect

There's a mod for Java servers that allows Bedrock players to join as well. https://github.com/GeyserMC/Geyser

Geyser: Download Geyser

Geyser is a plugin that you can install on your server to enable crossplay. You can download it from their official website or from their GitHub page. There are different versions of Geyser for different types of servers, such as Spigot, Paper, BungeeCord, Waterfall and more. Make sure you download the version that matches your server type.

She plays bedrock edition on her iPad. MacOS only supports Java edition. You need something like Geyser to play together or use software like Parallels to install windows on your Mac so you can play bedrock.

geysermc is a plugin that allows bedrock players to connect to Java servers https://geysermc.org/

In case you're willing to give it a shot, see: https://geysermc.org/

Its a plugin called GeyserMC that lets Bedrock players join Java servers.

Geyser: Geyser is a proxy that lets Bedrock Edition players join Java Edition servers. It supports most Java features and cross-play between different platforms. You can use it as a plugin or standalone proxy. You can download Geyser from here and join their Discord for support here.

That being said you can just deploy it yourself and not use someone elses.. https://github.com/GeyserMC/GeyserConnect

I only have experience using Geyser on a server so I don't know much about this, but you can look into GeyserConnect.

If you have a computer handy and a Java Edition account, you could try GeyserConnect (watch out if the server has an anticheat, anticheats don't like it). Otherwise, I'd just ask the owner to set up Geyser and Floodgate.