Young, Naive with questions galore

Evening Guys,

Straight out I'm a complete newbie. (YES ONE OF THOSE POSTS AGAIN) I'm Not a rookie in terms of not knowing what a GLSO is or a CFD or MACD or anything in that light. I've been very thorough with my research these past months and have gotten to learn (at least I think) all the terms. Never the less I want to learn the profession of trading.

I've been looking for the best broker for CFDs (Yes I know. Highly risky and unpredictable. You can lose more than you work with.) I have a low amount of spare cash (which I'm willing to lose in the name of experience) which is why margin trading would be my best bet.

I've considered CMC or IG and Traderdirect365. My main question has come from watching traders online who use very simple and somewhat ancient looking trading platforms. I did research and found Metatrader to be a popular result. I want to know what is the difference between using a downloadable platform vs using a brokers platform? How do you connect yourself with a broker via a downloadable platform? What is the best platform for me? What is the deal with all these platforms? If I wanted to go and learn and utilise algorithm trading what platform is best?

I'd appreciate any help.

Cheers

Blaz