Are there limits on which coins I can trade?

You can trade 700+ USDT pairs, including majors, altcoins and tokenised stocks and metals.

Low-cap coins (market cap under $100M, 24h volume between $500K and $5M, or Innovation Zone listings) are limited to 5% of your initial balance in total, including leverage. They move on thin liquidity, and a large position in one can wipe out an account in a single candle.