this server doesn't work on bedrock edition and to claim land you need to collect some money and then you can do /f money deposit [amount] to deposit some money into your faction. then you can either do /f claim auto to claim chunks wherever you go (say command again to turn off auto claim) or you can do /f claim [radius]
You only need to deposit a chest to make a land claim. The gold blocks that act as the border of your land claim will be visible on all four sides. You only have one land claim chest, but you can receive more in the future.