When they say HomeKit are they talking about like a hub “Home google or alexia? I don’t want to use a hub just our iPhones

Me and my husband are building a new house in Florida and our ceilings are vaulted about 18 ft in kitchen LR would like to be able to control lights ceiling fans in that area by using one app on our iPhones and also a switch on the wall (smart switches is what I have read to get) but when they say in this article HomeKit are the talking about a hub like mini home google or alexia or is this the kit to buy to that will connect to app on my phone this is new to me and my husband also when the electrician comes to wire our home is there any extra wiring to be done or something special that has to be done? We will have about 8 can lights total between kitchen and LR then about 3 hanging ceiling fans. Would be nice if could control A/C on the same app if possible thanks in advance Donna