Okay so I have a wife and two kids but I want more kids I know you can only have two kids maximum per household but i searched it up and I could have many kids in the game and I have many different houses but I can't have anymore kids why?? Help me get more kids please

You are adopting two children, your house is not adopting them, so it makes no difference how many houses you have, you have to nominate a family home and that is where the children stay. You want more you would have to play the PC version which would have a mod to adopt more. And the Hearthfire spoilers section would be the place to ask questions about Hearthfire.