Remove cover plate on side of track frame, just in front of drive sprocket. You'll find a grease fitting in there. Pump grease into fitting and it extends the track adjusting cylinder. I just tighten the tracks until there's a little sag in them, don't tighten until there's no sag.
Not sure about the oil change quantity. Somewhere around 1 3/4 gals.
Hyd oil level is a sight glass on left side of machine. Below cab and above rubber track. Might be covered in dirt right now. Add oil at back of machine. Raise the perforated grille above engine, where radiator and oil cooler is. You'll find a filler neck in there for hyd reservoir.