Depends what kind of modeling you are looking to do.
Anything organic, go Sculpting. I recommend using Dyntopo Mode. The tools are very few and super easy more or less. The workflows are divers. Bottom line, it’s all about your artistic sculpting skills.
Hard Surface, start watching then buy and test your favorites:
SpeedFlow
HardOps
MESHmachine
Creative Bundle Add-on
Start with videos that are most recent, as all of these addons are in constant rapid development. Check their Youtube channels.
All of these addons do similar things that were piloted by masterxeon1001 (the man behind HardOps), but each of them have unique twists and workflows.
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Tutorials, I’d recommend:
Hard-surface Modeling in Blender by Gleb Alexandrov and Aidy Burrows
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As icyou520 had mentioned, it’s bit of a transitioning time in blender. A lot is about to (officially) change real soon. Having said that, any learned skills are easy translatable. I’m quite positive that all of these addons are gonna be among the first to be released on 2.8, so that translates as well.