I cut my teeth using AutoCad (mostly 2003 IIRC), and I have to say, that Draftsight is VERY close. There are some minor command differences here and there, but there's a lot of cross over, and it's very fully featured. For the price, (free) you can't beat it.
For 3d modeling, Fusion 360 (also free) has everything you could ever ask for as well, though I'd make sure your computer was up to snuff for 3d rendering, as it can be a bit of a resource hog.
There are plenty of forums and youtube vids if you get stuck on something..