Lots of states want the foundation stamped by an engineer so they would check soil and footings be it slab on grade or foundation walls dug down under frost line.
States have very different permit requirements and inspection etc.
Best bet might be to start talking to a contractor first as they will know people who can help and they may have a ood idea of what is possible or not.
I mean just because you drew that roof and open concept does not mean it is practical to build as it could add costs you do not want to pay.
Some lumber yards will help you with sizing framing members or LVL or PSL etc.
My suggestion is to first find a GC and start talking and working out a deal on what he would require to build your house.