Darren is very right- the videos you are watching are likely referring to the Windows presentation of LT 2017.  You will want to either find videos showing the Mac presentation (as Darren says, it is NOT the same as the Windows interface) or run Windows on your Mac so you can use the Windows version of LT.

The firm you are going to work with, do they use Mac or Windows versions of CAD?  That is probably the place to start; make sure you are using the same operating system, or you will not have built the base of knowledge you want and they expect.