Ipad used as Homekit Hub.

Hi, I have been looking to use my ipad as a Homekit Hub.

The IOS is up to date, I have two stage authentication turned on and I have keychain turned on.

Problem is that Homekit doesn't display in my setting for me to be able to set it as a hub? (also doesn't seem to appear here as a topic for discussion).

I only got into this as I had recently purchased a nest doorbell and stat, they have a very good app on there own but id like to have the option of Homekit for other features in my house without going down the route of the g*@gle minis

any ideas?