Brandon98ML320

Hi I just bought a 98 ml320 and already have a few issues. First there is oil leaking from underneath the oil pan. Also after checking the fluids there is no dipstick for the transmission fluid.the coolant was almost empty so I added some from work, unfortunately I didn't know you were supposed to use only MB coolant. I just got this truck and I don't know much about cars. My friend said he will help but does anyone have any advice please? What tools do I need to get my friend to take apart the oil pan? Thank you
Brandon 1998 ML320