There are a multitude of General Contractors that will construct your home.
Cargill being one off the bigger names. That company has architects on staff.
There are hundreds of paper back books available with house plans. Or a simple sketch drawing of what you want.
Depending on your budget. A 3 car garage is advantageous. Or just a simple rectangular box with no garage. If older folks then a single story home has many advantages. No stairs to climb to bedrooms.
Water in basement can be a serious issues in some locations. The surface water table rises in Spring is some places and cause basement flooding issues.
Read up on perimeter drains. And triple up on those. Won't be done unless you ask.
Ice of roofs is an issue in many homes up here. Drive around in winter time and view homes. Many will have icicles hanging from roofs. Many/most/some builders do not know how to properly ventilate a roof.
Metal roof versus shingle roofs. Pros and cons on both. But overall a properly installed quality metal roof will never leak and will last forever or thereabouts. Note. I have seen two generations of bad asphalt roof shingles fail prematurely. Any warranty on roof shingles only covers the cost of the actual shingles - not the replacement cost of roof.
A quality whole home generator installed at time of construction is a good idea.
Views on heating systems vary greatly. Do some research on this topic. Find the method and brand that has the least breakdowns. The most simple to maintain and to repair. Whole house air conditioning is nice but can be expensive. A Mitsubishi (or other brands) added split heating/cooling is a nice redundant added back up for at least one room. Then there are wood fireplaces, gas fireplaces, and pellet stoves as an added redundancy system.
Low voltage wiring sometimes called structured wiring. Few builders even understand this. The house should be hard wired with RG6 and Cat5e/Cat6 wires to every room terminating in a low voltage panel. Determine where the modem and router are to be placed. Usually should be in center of home and not hidden in a corner of the basement. Most will state that everything is "wireless" now. Hard wiring is faster and safer then wireless. All routers today do have wireless capabilities. Hard wiring is always better.
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Wire for home theater or sometimes called surround sound. The quality of the sound from the television improves dramatically with built in wall/ceiling speakers in living room/TV room.
Double up on the number of electrical outlets. There are never enough. Place one on each exterior wall.
Of course quality of windows and doors. Anderson for example makes 3 grades of windows.
Lots of things to consider. Don't assume anything. One has to become familiar with all facets of home construction to make sure what is built is what one expects.
If time and funds permit attend the International Builders Trade Show IBS
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You will find a wealth of information at this trade show. Only open to the trades but there are ways to get admission if one digs deep. Been to this trade show every year. This is NOT a Home Show that one would go to locally. This is the largest building trade show in the world. Well worth the effort if one is going to have a home built.
Good Luck.