Ask, ask ask, lots of help here.
But first, the ITG's "Interactive Training Guides" ...
Go to > Help > Training Guides, clicking here takes you to the GS webpage. There you will see several interactive training guides. These are guided tours, with a separate tour for each of several subjects. They come with a PDF file with complete step by step, but wait there's more!, they also come with tons of short video clips showing you exactly where commands can be found and and what happens when it is done right. Indispensable, must see stuff.
I am a sole practitioner, I went down the "hire the guru" path. It did help kick start the process. But I should have done all the training guides first. The training guides should not be missed. After you do the guides (or as you do them) use this forum, and by all means contact that guru. Without the forum I would now be using other software. Additionally check the GS webpage under events, they sponsor one week "schools" on AC, if you're looking @ $600/day for your guru, these school workshops will seem cheap to you.
All your questions about the footer, walls intersecting are in the first ITG's you should do: Experience BIM, Essentials and Advanced Modeling, the one on GDL is really good too.
Gaining the virtual modeler's "mental approach to the problem" was my biggest failing, I too had over 20 years of AutoCad then Microstation" 2d way of doing it" that simply crippled my ability to quickly get to it as a modeler who expects great 2d output as well.
Snap
PS Our vendor has monthly online training classes, they focus on one topic, but you'll learn how a really good user thinks when approaching an issue. Check with your vendor, and pay for the subscription service. Elsewhere on forum you will hear people gripe about buying the yearly upgrade; listen, its the support, online training, etc that you get that is why you should pay the yearly fee IMHO. Who knows, maybe one day you might change your moniker from cadmaster to modelmaster.