It really depends on what program(s) you’ve used in the past. Online CAD program training may be a good option for you.
If you’ve used anything AutoCAD-based (such as Land Desktop, Eagle Point, Civil 3d) then the only thing you will need to learn is how Carlson manages points or surfaces compared to those programs. In many ways Carlson Software and Land Desktop are more similar than Land Desktop and Civil 3d so the learning curve is pretty short.
But, if you’re coming from TerraModel or Microstation-based program, learning the AutoCAD or IntelliCAD platform underneath Carlson programs will probably double the time it takes to learn the program. It’s all CAD so you’re not starting from scratch, but figuring out the fundamental differences between layers and levels, templates and seed files, cells and blocks, paper space and plan/profile views and so on will take some time.
Refer to this FAQ for training that’s available if you need to learn CAD or Carlson Software.