Jeremywell Torque Converter Go Kart Clutch kit 30 Series 1 inch 12T #35 Chain

Q: Does the driver clutch have a 1 inch bore or 3/4 inch bore?

The driver(engine side) has a 1” bore, the driven(sprocket side) has a 5/8” bore.

Q: I need to buy a belt for it so what size is it

https://www.amazon.com/gp/aw/d/B06Y12QPPJ?psc=1&ref=yo_pop_mb_pd_title

Q: will the converter fit the predator 212CC engine?

No this will not fit a Predator 212 as to my knowledge they have a 3/4” shaft. Now this could work with a bushing but that would have to be a 1/4” thick bushing which finding one would be tough, but making it work with a woodruff key would be challenging. It could be done, but for the effort involved it would be a much easier and more cost effective choice to get one with a 3/4” bore.