I have tried 2 or 3 of the free cads and none of them seem simple , my son does not see why I have such a hard time( he's working on his doctorate in a engineering field I can't even pronounce) then again I learned to draw with French curves ,parallel bars and a T square.
I've had turbocad for years and it's well supported and documented. It works well for a low cost 2D. Draft sight is a free Autocad clone and is very capable but there's more to learn. Watch all the videos you can. It's the fastest way to pick up all the ways to use the commands.
I used Alibre (now Geomagic) for a few years and it's an OK entry level 3D program. I switched to Solidworks a few years ago and it really put me through the wringer to learn but it's been very useful for me after I half way got it figured out. I hope to learn the other half of it some time.
After 40 years of drafting experience, I use a #2 pencil, not kidding. My son is an architect in Boston and he uses pencils as much as he does CAD. It is a must for him to be able o use the board with a pencil. He also uses colored pencils. He is the senior architect at his company in designing surgery centers in hospitals.