1997 Oldsmobile Bravada Smoke / Check Gages

I saw smoke coming out from the car's hood, after I came back home. When I propped it open, I saw signs of oil leaks, which was getting evaporated from the hot engine parts. There was also oil leakage under the car, in the same area.
I, then, checked the engine coolant reservoir, and found it to be empty. Hence I suspect a leak somewhere which drained all the engine coolant.

I also had "check gages" sign, where the temperature shot up in the "red" and the oil pressure was decreasing. However, on pressing the accelerator, the oil pressure increased, but it was way below the normal.

Are the above two problems related? How can I go about diagnosing the exact cause? Is there a way to fix it?