Sit and Go Wiz can be used on your system but not while playing a game. Thats software is excellent for your offline training. I would highly recommended the quiz feature in it.
As good as HEM and PT3 are, for starting out you may find them too daunting, even overwhelming with data and set-up procedures that can bury you before you even get started.
I would recommend sticking to the basics, especially if you are playing the lower limits at any site. To that end for sit and go tournaments your best option is Tournament Indicator and they too have a free trial with some easy to follow video tutorials for getting started.
Actually the quiz mode in Wiz is really awful, because the default ranges are so inaccurate. You could train yourself into making the wrong plays.
The best way to learn with SNGWiz is to set up a filter in HEM/PT3 (works best with HEM but you can still do it with PT3). This filter can sort by the number of people in the hand, your position, your stack size, etc. For example, you can filter for all
hands where you have 6-8bb's in the CO and the table is 6-handed. This way you control just a small number of variables and you can actually see how they affect your shoving ranges, rather than trying to figure out from a million different variables in the game review mode.