Wow, so happy to see you. I stumble upon this video seeing the face , i said this face looks familiar. Emmanuel is a very honest and God fearing man. He helped me many years ago on a building plan.. I will try your number today i hope it's still the same. I have subscribed.
The walls should emanate from the foundation, and it is your engineer or builder that will determine the ones that shouldn't (if there is any) depending on the load bearing capacity of the soil.