A small selection of the resources available to learn about the various software packages that make up the 3D printing workflow.
The TinkerCAD website has several good tutorials, and there are a wealth of good videos on YouTube.
Meshmixer is a tool for editing and repairing 3D triangle meshes such as you get from 3D scanners or models not originally designed for 3D printing. It can also simplify models, shrinking the .stl files and making slicing faster.
Slicers are used to convert .stl files into g-code for the printer. You can create sets of custom settings for your specific printer called a profile.
There is endless information available on the Simplify3D site. Like many other packages the Simplify3D folks also have a YouTube channel.
Used to send designs to a directly connected printer. Provides a way to control printer directly, setting temperature, fans, homing the axis. Loads g-code files into the printer and monitors the progress of prints.
It's somewhat hard to separate the MatterContol tutorials into Modeling, Slicing or Monitoring as most tutorials cover all three.
OctoPrint provides a web accessable interface to your printer. It is popular to install the OctoPrint monitoring software on a RaspberryPi called OctoPi. There are lots of helpful people on the OctoPrint Community Forums. Several slicing programs have OctoPrint integration built in.