You have fixed floats and the ones that has a thin flexible metal plate. If fixed, nothing to adjust, valve tip must seal & sit fully on valve seat when pushed upwards by float. Float body must rest parrallel to carb's border when turned upside down, adjust if needed.
Carb adjustments must be done while OB works with boat at sea, lake, river, whichever. Adjusting mixture/idle screws on muffs/ barrel will vary than when combo is adjusted as suggested. Mixture screw will only adjust ralenti speed, when throttle is opened up, carb works with fixed non adjustable jets. Go for a spin at 3/4 throttle for some minutes for OB to reach its working temp and then adjust both screws.
All non synthetic 2 strokes TCW-3 oils do smoke, more at first start, less when OB is working at its correct temp. 2 strokes OB's doesn't like working at idle/fast idle speeds for long time periods, plugs foul faster due to plug tip not reaching higher temp that's only reached while running at much higher revs.
Happy Boating