To find it, you'll need to:
1. Identify your transmission: Look for a tag or marking on the transmission itself. This will give you the specific model number.
2. Consult a repair manual: Once you know the transmission type, find a repair manual (Haynes, Chilton, or a factory service manual) specific to your Jeep Wrangler's year and transmission. The manual will have a diagram showing the location of the fill plug.
3. Look on the top and sides of the transmission: The fill plug is usually on the top or side of the transmission case, often near the top of the shift linkage. It's usually a threaded plug and might be slightly different in size and shape from other bolts.
Without knowing your specific transmission type, I cannot give you a precise location. Trying to guess could lead to you stripping a bolt or adding fluid to the wrong area. Using a repair manual is the only safe and reliable way to locate the correct fill plug.