Q.Indoor avocado tree
I am growing an avocado tree from a seed. It’s growing well but not branching. It gets 3 leaves at the top. As more come out of the top, the 3 that are there die and fall off. How do I get it to branch?

It appears that your Avocado plant needs more sunlight. Increase the light that your plant is receiving and as it grows more leaves you can began to pinch off to create a bushier plant.
Here is a link with care information.
https://www.gardeningknowhow.com/edible/fruits/avocado/indoor-avocado-plant-care.htm