Does anyone know of a website I can access to design a home?

I’m looking to build my home and I will meet with a designer in a few days. I know this is what I’m paying him for but I want to go in knowing exactly what I want and how I want and have him tweak it not go in with unrealistic ideas and spend a lot of time and money him saying not doable. Even if its a paid for site, I would appreciate it so long as its easy to access and navigate Free of course would be better.