Q.Avocado Leaves Curling
My husband and I have been able to grow an avocado plant from a pit we cultivated from a store brought avocado. It is currently about 10 inches tall. We moved it from a smaller pot to a bigger pot about 2 months ago. It is in the corner of a room with A LOT of windows. When the topsoil gets a little dry, I’ll water her with room temperature water. When the water begins to pool in the bottom tray, I stop and remove the excess water from the tray. Recently, the leaves began to curl in on themselves.
QUESTION: What could possibly going on that we can fix? Is it getting too much water? Too little water? Not enough sun? etc. etc.

The leaf curling is likely due to overwatering.
You can adjust the watering and stop watering before it begins to run through the pot.
Make sure the soil is a good loamy mix.
The link below will refresh you on the care requirements.
https://www.gardeningknowhow.com/edible/fruits/avocado/indoor-avocado-plant-care.htm