With reference to my post https://www.prorealcode.com/topic/multiple-strategies-within-one-trading-system/, you can achieve your goal with this modified version. I only coded strategy #2, but you need to apply the same logic to strategy #1 and #3:

DEFPARAM CumulateOrders = TRUE        //Allow multiple trades at a time
IF NOT OnMarket THEN                  //Make sure you reset these variables to ZERO when not trading
   P1 = 0
   P2 = 0
   P3 = 0
ENDIF
//--------------------------------------------------------------------------------------------------
IF P1 < 1 THEN					                               //Strategy 1
   .
   .
ENDIF
//--------------------------------------------------------------------------------------------------
IF P2 < 1 THEN					                               //Strategy 2
   s2Avg = Average[20](close)
   s2Rsi = Rsi[14]
   .
   .
   .
   //************************************************************************
   //                                 LONG
   //************************************************************************
   IF close CROSSES OVER  s2Avg THEN
      SET TARGET PPROFIT 20
      SET STOP PLOSS     10
      BUY nLots CONTRACT AT MARKET
      P2 = 1                            //set P2 to 1 to disable further trading this strategy
   ENDIF
   //************************************************************************
   //                                 SHORT
   //************************************************************************
   IF close CROSSES UNDER s2Avg  THEN
      SET TARGET PPROFIT 20
      SET STOP PLOSS     10
      SELLSHORT nLots CONTRACT AT MARKET
      P2 = 1                            //set P2 to 1 to disable further trading this strategy
   ENDIF
   .
   .
   .
   .
ENDIF
//--------------------------------------------------------------------------------------------------
IF P3 < 1 THEN					                               //Strategy 3
   .
   .
   .
ENDIF