It helps dissolve and reduce carbon buildup in the motor. It is not a fuel stabilizer. I use it every gas up at a ration of 1 oz per 10 gals of gas. The reason they call it ring free is that it reduces buildup that could clog the ring groves. That causes the rings to bind and than can lead to ring breakage and extensive motor damage. The stuff is not cheap though costing about $35 per 32 oz bottle last time I bought it.
I don't have carbs but I do fog my cylinders. For either, add stabilizer to the gas and run the motor to get it into all the bowls, filters etc. Then you can fog the carbs by following the instructions on the fogging can.
Many folks at my club do not run the carbs dry since that can cause gaskets to dry out, shrink and eventually leak. That is especially true for some older motors. Running dry also causes the motor to run lean towards the end of the running and that can be an issue. So my advice is follow the instructions on the can