This could as easily be a physics or chemistry question, so I would like to avoid this conversation in the comments.
I would like to know the general method of converting between units. For example converting Joules to $\frac{g\cdot cm^2}{s^2}$
I assume it's possible because the SI unit of energy is $\frac{kg\cdot cm^2}{s^2}$ so is it as simple as going from J to $\frac{kg\cdot cm^2}{s^2}$ and then times 1000 to get $\frac{g\cdot cm^2}{s^2}$?
If so then how does one know how many J in 1 $\frac{kg\cdot cm^2}{s^2}$? Is it something you have to learn like 1kg is 1000g?
The idea is to look at some equations which involve the quantities you are interested in. So the definition of Joule is the work done by a force of $1N$ moving an object for $1m$. Then you need to know what a Newton is. From Wikipedia "One newton is the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force." Therefore $$1J=1N\cdot 1m=1kg\cdot1\frac{m}{s^2}\cdot 1m=1kg\frac{m^2}{s^2}$$