It really depends on what you are trading. Are you trading spreads or binaries? Intraday contracts or daily contract’s? There really is no “best time frame” when it comes to trading. The answer to your second question is definitely yes, it depends on the type of contracts that you are using. You don’t want to use a 15 minute chart to trade 5 minute binaries. My best advice is study up on the systems offered here at Apex, learn one and master it and trade that.
Good luck.
Peter