Number of indicator flashes is either 1 or 3 - adjusted via the buttons on the indicator stalk when the engine is running ... you really will have to read the instructions I'm afraid ! You just get into a menu, then a sub menu displayed where the odometer is on the dash and pick what you want.
Beeping - no way of changing volume that I know of.
Having come from a 330d LCI with idrive I found the E89 without it a bit tedious. Once set up though it is not something you revisit.