I kinda spent some time reading the documentation but i still can't understand how to apply an indicator like sma to stDev.

double dev[] = indicators.stdDev(instrument, period, myOfferSide, IIndicators.AppliedPrice.CLOSE, stDevPeriod, nbDev, Filter.WEEKENDS, candlesBefore, currBarTime, candlesAfter);
// and here we call the sma.... But how
double ma[] = ?????

is it

indicators.calculate()

or can i do

indicators.ma(.....);

???

You can do it in both ways, here is more information about indicator calculation in your strategy: https://www.dukascopy.com/wiki/en/development/strategy-api/indicators/indicator-calculation

SMA named method:

        double smaNaming = indicators.sma(
                Instrument.EURUSD,
                Period.TEN_MINS,
                OfferSide.BID,
                IIndicators.AppliedPrice.CLOSE,
                14,
                0
        );

SMA with universal calculation method:

        Object[] smaUniversal = indicators.calculateIndicator(
                Instrument.EURUSD,
                Period.TEN_MINS,
                new OfferSide[] {OfferSide.BID},
                null,
                "SMA",
                new IIndicators.AppliedPrice[] {IIndicators.AppliedPrice.CLOSE},
                new Object[] {14},
                0
        );