You can trade with leverage or without, because you decide exactly how much risk exposure size of all your trades. To not use leverage, you can trade using 1:1 (or less) of your constant trading power in USD to your USD value of account balance in cryptocurrency.
For example, if your account balance USD equivalent value is $100 and you open a position for $100, you would be trading exactly 1:1 of trading power to your account balance and thus not using leverage. Then, if you decide to open trades for a total $1000 position size, you would now be trading 10:1. It is entirely your choice to use leverage or not, while trading at real-time spot prices of relevant global exchanges with absolutely no commissions and borrowing fees of any kind.
Keep in mind that the USD value of your account balance in cryptocurrency, such as ETH for example, will be affected if the value of ETH appreciates or depreciates due to the market price fluctuations of ETH/USDT pair. Keeping your account balance funded in stablecoin will avoid any such fluctuations.