Yes 0.02 lots is 2 oz (for XAUUSD).
Hope you realise that the silver contract is a big one. If you can't trade gold profitably don't try silver.
My suggestions:
Don't try to scalp as your costs will be a huge hurdle to overcome. Try to target good R/R trade setups.
It's easy for me to point out the importance of good R/R but it's very difficult to stay in a trade when volatility increases suddenly.
Be aware that the commodity markets move during the UK session and can be very volatile during the US session (esp. 1hr before US open). Don't start a trade with a tight SL just prior to news or the start of the UK,US sessions.
The only thing that will help you stay in the great trades is a set of rules that you know works.
Your success will be determined by your trade management once you start a trade.
Start trading in only a few markets at first. Look at others when you are consistently profitable in your favourites. Commodity markets move when you are not looking at them (lol).
I would add good luck, but you really need to have a solid trading plan and an excellent grasp of risk management before you start.