I guess it never hurts testing out software. When I began trading all the "complicated" tools in my thinkorswim trader felt scary. But if you spend a lot of time analyzing companies and browsing economic news, why not learn using those tools in your advantage. I suggest you begin with the basics and move up from there. Learning it all at once is a bit overwhelming. All the best
But how do they determine the entry point? You need software to do that unless you are some kind of a fundamental or random trader. Then what you say applies solely to position trading.
The obvious answer is, some people use a trading approach that requires no software at all, while other people use a trading approach that does need software. Whether or not YOU need software, depends on your trading approach. Obviously. A delightful example of a profitable trader who requires no software at all: http://tinyurl.com/3dx9uk
The best and cheapest (free) combination of data and platform is Ninja Trader with zen-fire feed for US and EU futures. You can download Ninja directly from their website NinjaTrader.com. They also have great support forum. zen-fire feed is provided by mirusfutures and ampfutures, they will also send you ninja download link and license key. You do not even need to open an account to get live data, just register for demo. Zen-fire is of the best and fastest needs. Ninja is free for charting and demo trading. There will be no need to learn anything else.