You can play Obsidian-Prison by adding the server in the Minecraft launcher.
On Minecraft Bedrock Edition, open the Minecraft launcher or Minecraft app. Go to the “Servers” tab and press “Add Server.” Enter the Obsidian-Prison IP Address obsidian-network.myserver.gsin the “Server Address” and the Obsidian-Prison port 19132 in the “Port.” Then press “Save” and start playing.