If engine is water-flooded, it must be serviced within a few hours after it being flipped. Otherwise engine might be screwed.
Check fuel and oil reservoirs for water contamination. If necessary, siphon and refill with fresh fluids. Turn fuel valve to OFF position then drain fuel filter
bowl.Drain bilge if water is present. Remove spark plug cables and connect them on grounding post. Remove spark plugs and dry them. A contact cleaner spray can be used. Crank engine to drain get all water out of it. Spray WD40 in spark plug holes after getting all the water out. Put new plugs in a give it a try. If it doesn't start then do all the above again.