You may want to take a basic look at how currents and voltages add up in series and parallel, and maybe read up on the basics of transistors. You can google them and there should be many university websites with lectures/notes. You'll probably understand better what you are doing. I'm not sure any of us want to type up a lecture on how basic electrical theory or transistors work.
In terms of specifics, I would select an appropriate range of Collector currents in your search and work from there. Your voltage limitations are unlikely