There are different ways to configure your buy amounts in the Base config under 'Coins and amounts' of your trading bot. Do you want to open trades based on a percentage of your funds or do you rather have a consistent order size?
Percentage of your funds
If you prefer trades to be opened based on a percentage of your balance, you can use 'Percentage buy amount'. Determine the percentage of your balance, and the trading bot will open positions based on this percentage. Ensure that when you want to trade based on a percentage, the 'Minimum trade amount' should be lower than the Percentage buy amount.
Consistent order size
If you prefer orders to always have exactly the same size, you can choose to use 'Minimum buy amounts'. For example, set your Minimum buy amount to 1000 USDT. In this case, ensure that the 'Percentage buy amount' is lower than the 'Minimum trade amount'.