Hi Feri, sure, you can customize your own trading strategy. There is no need to code, it's much easier than that. For example, there is a parameter called STOP_LIMIT, you can set it to 5, and the bot will sell if the coin it purchased drops its value by 5%, other example, the parameter GAIN, set the minimum profit % for a trade, that is, if you set GAIN to 6 and the bot purchased a coin for 100, it won't sell it until the price reach, at least, to 106. You can create very advanced trading strategies just by changing parameters.
On the other hand, if you also get TradingView Addon for Gunbot, you also have the option of coding a trading strategy from scratch using Pine Script. This option requires some coding skills unless you decide to use TradingView Addon for executing alerts from other traders from tradingview.com.