Looks like it is time for you to buy a repair manual such as a Haynes or Gregorys, these will help a lot.
If you are in no position to get a mechanic to do it, you need to start learning really quickly.
Do not use additives, they will cause bigger problems in the long run.
You probably have multiple leaks there, but always remember oil doesn't leak upwards, so always start looking at the top.
For you to have oil leaks that far up the engine at the rear, pay particular attention to the valve cover seal and and the distributor o-ring. If you don't know where these compnents are, Google 5S-FE followed by the component mentioned and click on images.
You may also have have a leak from the timing belt region as well. It's really hard to tell, so degreasing the engine will help to clear away a lot of this oil, then keep an eye on where it is coming from.
In regards to the coolant loss, there is a good chance it is coming from the water pump.