Yes, get the nanual, and what you are looking for is in the maintenace and lubrication chapter.

The drain plug for the tranny is in the pan, and the fill plug is above the dside of the pan about halfway up the side of the case, maybe a tad lower.

Any plug with a spring is a detent poppet plug that engages a notch on the shift rods to stop it in each gear position.

The transfer case has it's own drain and fill plugs. Both are on the chain case of the tcase, the finned oval aluminum casting that runs from the rear driveline centerline to the front driveshaft centerline. The drain plug is near/at the bottom, facing rearwards if memorty serve. The fill plug is maybe 4" higher, and on the sideish?

In the case of the tcase for sure, and preferably for the tranny, be very sure you can take out the fill plug before you open the drain plug. The fill level is to the bottom of the fill hole.