SC cells will take fast charging and have reasonably low internal resistance. SCR cells have lower internal resistance and a somewhat flatter discharge curve, that is, they put out nearly the same voltage from beginning to end of the discharge. SCRs are best for high current drain applications. SCE cells have somewhat more capacity for the same physical size, but also have higher internal resistance. The higher capacity of SCE cells will not be realized at high current drains, and they will heat up more than SCR cells.
Many kits nowadays come with a power system.
In most cases, these systems are adequate for the application. It won't hurt to try what's there to start with, you can always experiment later. If the kit you choose doesn't come with a motor, of course, you'll have to choose one. If you are a beginner, go with the recommendations of the kit manufacturer. If you are an experienced RCer, you probably don't need my help.