This is what I used to design mine
https://carolinacarportsinc.com/color-planner
I got it through a dealer that is in Lexington where 378 and US1 seperate.
Always pay extra for the wind rating stuff. Living in Florida it is ingrained.
You will have a seperate company pour the slab. Then the metal fab people installers will come in and put it together.
Then you have electric run to it. I had a 200 amp service run, but i wired up all my lights and internal stuff to the panel.
I would recommend adding LeanToos on the sides now, rather than doing it later. I should have done it before becuase it is great to have them.
have extra concrete poured on the front so your doors are not right into the grass/dirt
And i used radiant barrier on the walls which reduced surface temperature by 40 degrees.
And last I was super OCD and caulked all the seams.